An Idolatrous Nation or an Enslaved People: Where Does the Jewish Story Begin?
Mishnah Pesachim 10:4
מָזְגוּ לוֹ כוֹס שֵׁנִי, וְכָאן הַבֵּן שׁוֹאֵל אָבִיו, וְאִם אֵין דַּעַת בַּבֵּן, אָבִיו מְלַמְּדוֹ, מַה נִּשְׁתַּנָּה הַלַּיְלָה הַזֶּה מִכָּל הַלֵּילוֹת...וּלְפִי דַעְתּוֹ שֶׁל בֵּן, אָבִיו מְלַמְּדוֹ. מַתְחִיל בִּגְנוּת וּמְסַיֵּם בְּשֶׁבַח, וְדוֹרֵשׁ מֵאֲרַמִּי אוֹבֵד אָבִי, עַד שֶׁיִּגְמֹר כֹּל הַפָּרָשָׁה כֻלָּהּ:
They pour the second cup (of wine), and here the son asks his father (the four questions). If the son is ignorant, the father teaches him: Why is this night different from all other nights?...The father should teach his son according to the son's intelligence. He begins with disgrace and concludes with glory, and teaches the entire passage of ארמי אובד אבי.
Bavli Pesachim 116a
מַאי בִּגְנוּת? רַב אָמַר: ״מִתְּחִלָּה עוֹבְדֵי עֲבוֹדָה זָרָה הָיוּ אֲבוֹתֵינוּ״. וּשְׁמוּאֵל אָמַר: ״עֲבָדִים הָיִינוּ״.
What is disgrace? Rav says: "Originally, our forefathers were idol worshipers". Shmuel says "We were slaves (in Egypt)".
Rambam, Hilkhos Chametz u'Matzah 7:1-2
מִצְוַת עֲשֵׂה שֶׁל תּוֹרָה לְסַפֵּר בְּנִסִּים וְנִפְלָאוֹת שֶׁנַּעֲשׂוּ לַאֲבוֹתֵינוּ בְּמִצְרַיִם בְּלֵיל חֲמִשָּׁה עָשָׂר בְּנִיסָן...אֲפִלּוּ חֲכָמִים גְּדוֹלִים חַיָּבִים לְסַפֵּר בִּיצִיאַת מִצְרִים וְכָל הַמַּאֲרִיךְ בִּדְבָרִים שֶׁאֵרְעוּ וְשֶׁהָיוּ הֲרֵי זֶה מְשֻׁבָּח:
...לְפִי דַּעְתּוֹ שֶׁל בֵּן אָבִיו מְלַמְּדוֹ. כֵּיצַד? אִם הָיָה קָטָן אוֹ טִפֵּשׁ אוֹמֵר לוֹ בְּנִי כֻּלָּנוּ הָיִינוּ עֲבָדִים...וּבַלַּיְלָה הַזֶּה פָּדָה אוֹתָנוּ הַקָּדוֹשׁ בָּרוּךְ הוּא וַיּוֹצִיאֵנוּ לְחֵרוּת...
It is a positive Biblical commandment to tell of the miracles and wonders which our forefathers experienced in Egypt on the night of the 15th of Nisan...Even great scholars are obligated to tell of the Exodus from Egypt, and all who elaborate on what happened is praiseworthy.
...A father teaches according to his son's intelligence. For example, if the son is very young or unintelligent the father should tell him "we were all slaves...and God liberated us on this night and gave us freedom..."
Rambam, Hilkhos Chametz u'Matzah 7:4
צָרִיךְ לְהַתְחִיל בִּגְנוּת וּלְסַיֵּם בְּשֶׁבַח. כֵּיצַד? מַתְחִיל וּמְסַפֵּר שֶׁבַּתְּחִלָּה הָיוּ אֲבוֹתֵינוּ בִּימֵי תֶּרַח וּמִלְּפָנָיו כּוֹפְרִים וְטוֹעִין אַחַר הַהֶבֶל וְרוֹדְפִין אַחַר עֲבוֹדַת אֱלִילִים. וּמְסַיֵּם בְּדַת הָאֱמֶת שֶׁקֵּרְבָנוּ הַמָּקוֹם לוֹ וְהִבְדִּילָנוּ מֵהָאֻמּוֹת וְקֵרְבָנוּ לְיִחוּדוֹ. וְכֵן מַתְחִיל וּמוֹדִיעַ שֶׁעֲבָדִים הָיִינוּ לְפַרְעֹה בְּמִצְרַיִם וְכָל הָרָעָה שֶׁגְּמָלָנוּ וּמְסַיֵּם בַּנִּסִּים וּבַנִּפְלָאוֹת שֶׁנַּעֲשׂוּ לָנוּ וּבְחֵרוּתֵנוּ...
One ought to begin with disgrace and conclude with glory. They should begin (by saying that) our forefathers in Terach's generation and previously were heretics who strayed after meaninglessness and chased false gods, and conclude with the true religion that God attracted us to, thus distinguishing us from the nations, attracting us to monotheism. Similarly, they should begin by admitting that we were enslaved by Pharaoh in Egypt and tell of all the bad things they did to us, and conclude with the miracles and wonders that were done for us, and our ultimate salvation.
Rambam Hagadah (from the end of Hilkhos Chametz u'Matzah)
נוסח ההגדה שנהגו בה ישראל בזמן הגלות כך הוא, מתחיל על כוס שני ואומר:
בבהילו יצאנו ממצרים. הא לחמא עניא דאכלו אבהתנא בארעא דמצרים. כל דכפין ייתי וייכול...
מה נשתנה הלילה הזה מכל הלילות...
עבדים היינו לפרעה במצרים, ויוציאנו יי אלהינו משם ביד חזקה ובזרוע נטויה...
This is the text of the Hagadah that Israel uses during the time of exile. Begin with the second cup and say the following:
We left Egypt hastily. This is the poor bread that our ancestors ate in Egypt. Whoever is hungry, come and eat...
Why is this night different than all other nights?...
We were slaves to Pharaoh in Egypt, and haShem our God freed us with a mighty hand and outstretched arm...

There are several retellings of the Exodus story in the Torah and Tanakh (apart from the original is in Shemos through Bo):

1) The text of ארמי אובד אבי in the mitzvah of bikurim at the beginning of Parshas Ki Savo (Devarim 26:1-11)

2) Yehoshua's account of all of Jewish history up to that point on his deathbed in the last chapter of Sefer Yehoshua

(See also Devarim 6:20-25, Yechezkel ch. 20, and Tehilim chs. 78, 105, and 114)

Devarim 26:5-9
וְעָנִ֨יתָ וְאָמַרְתָּ֜ לִפְנֵ֣י  ה׳ אֱלֹקיךָ אֲרַמִּי֙ אֹבֵ֣ד אָבִ֔י וַיֵּ֣רֶד מִצְרַ֔יְמָה וַיָּ֥גׇר שָׁ֖ם בִּמְתֵ֣י מְעָ֑ט וַֽיְהִי־שָׁ֕ם לְג֥וֹי גָּד֖וֹל עָצ֥וּם וָרָֽב: וַיָּרֵעוּ אֹתָנוּ הַמִּצְרִים וַיְעַנּוּנוּ וַיִּתְּנוּ עָלֵינוּ עֲבֹדָה קָשָׁה׃ וַנִּצְעַק אֶל ה׳ אֱלֹקי אֲבֹתֵינוּ וַיִּשְׁמַע ה׳ אֶת־קֹלֵנוּ וַיַּרְא אֶת־עָנְיֵנוּ וְאֶת־עֲמָלֵנוּ וְאֶת־לַחֲצֵנוּ׃ וַיּוֹצִאֵנוּ ה׳ מִמִּצְרַיִם בְּיָד חֲזָקָה וּבִזְרֹעַ נְטוּיָה וּבְמֹרָא גָּדֹל וּבְאֹתוֹת וּבְמֹפְתִים׃ וַיְבִאֵנוּ אֶל־הַמָּקוֹם הַזֶּה וַיִּתֶּן־לָנוּ אֶת־הָאָרֶץ הַזֹּאת אֶרֶץ זָבַת חָלָב וּדְבָשׁ׃
You shall then recite as follows before the LORD your God: “My father was a fugitive Aramean. He went down to Egypt with meager numbers and sojourned there; but there he became a great and very populous nation: The Egyptians dealt harshly with us and oppressed us; they imposed heavy labor upon us: We cried to the LORD, the God of our fathers, and the LORD heard our plea and saw our plight, our misery, and our oppression: The LORD freed us from Egypt by a mighty hand, by an outstretched arm and awesome power, and by signs and portents: He brought us to this place and gave us this land, a land flowing with milk and honey:
Yehoshua 24:2-5
וַיֹּ֨אמֶר יְהוֹשֻׁ֜עַ אֶל־כׇּל־הָעָ֗ם כֹּה־אָמַ֣ר ה׳ אֱלֹקי יִשְׂרָאֵל֒ בְּעֵ֣בֶר הַנָּהָ֗ר יָשְׁב֤וּ אֲבֽוֹתֵיכֶם֙ מֵֽעוֹלָ֔ם תֶּ֛רַח אֲבִ֥י אַבְרָהָ֖ם וַאֲבִ֣י נָח֑וֹר וַיַּעַבְד֖וּ אֱלֹהִ֥ים אֲחֵרִֽים׃ וָ֠אֶקַּ֠ח אֶת־אֲבִיכֶ֤ם אֶת־אַבְרָהָם֙ מֵעֵ֣בֶר הַנָּהָ֔ר וָֽאוֹלֵ֥ךְ אֹת֖וֹ בְּכׇל־אֶ֣רֶץ כְּנָ֑עַן (וארב) [וָֽאַרְבֶּה֙] אֶת־זַרְע֔וֹ וָאֶתֶּן־ל֖וֹ אֶת־יִצְחָֽק׃ וָאֶתֵּ֣ן לְיִצְחָ֔ק אֶֽת־יַעֲקֹ֖ב וְאֶת־עֵשָׂ֑ו וָֽאֶתֵּ֨ן לְעֵשָׂ֜ו אֶת־הַ֤ר שֵׂעִיר֙ לָרֶ֣שֶׁת אוֹת֔וֹ וְיַעֲקֹ֥ב וּבָנָ֖יו יָרְד֥וּ מִצְרָֽיִם׃ וָאֶשְׁלַ֞ח אֶת־מֹשֶׁ֤ה וְאֶֽת־אַהֲרֹן֙ וָאֶגֹּ֣ף אֶת־מִצְרַ֔יִם כַּאֲשֶׁ֥ר עָשִׂ֖יתִי בְּקִרְבּ֑וֹ וְאַחַ֖ר הוֹצֵ֥אתִי אֶתְכֶֽם׃
Then Joshua said to all the people, “Thus said the LORD, the God of Israel: In olden times, your forefathers—Terah, father of Abraham and father of Nahor—lived beyond the Euphrates and worshiped other gods: But I took your father Abraham from beyond the Euphrates and led him through the whole land of Canaan and multiplied his offspring. I gave him Isaac: and to Isaac I gave Jacob and Esau. I gave Esau the hill country of Seir as his possession, while Jacob and his children went down to Egypt: “Then I sent Moses and Aaron, and I plagued Egypt with [the wonders] that I wrought in their midst, after which I freed you:
Guide of the Perplexed III:39 (Pines p. 552)
As for the reading on the occasion of the (Bikurim), it also is conducive to the moral quality of humility...It contains an acknowledgment of God's beneficence and bountifulness, so that man should know that it is a part of the divine worship that man should remember states of distress at a time when he prospers...
Guide of the Perplexed III:43 (Pines p. 572)
These festivals...inculcate...a moral quality...(which) consists in man's always remembering the days of stress in the days of prosperity, so that his gratitude to God should become great and so that he should achieve humility and submission...
Sefer haChinukh Mitzvah 21 (and Mitzvah 5)
מצות ספור יציאת מצרים...משרשי מצוה זו: מה שכתוב בקרבן הפסח.
(מצות שחיטת הפסח...משרשי מצוה זו: כדי שיזכרו היהודים לעולם הנסים הגדולים שעשה להם השם יתברך ביציאת מצרים.)
ואין מן התמה אם באו לנו מצות רבות על זה, מצות עשה ומצות לא תעשה, כי הוא יסוד גדול ועמוד חזק בתורתנו ובאמונתנו...אות ומופת גמור בחדוש העולם, וכי יש אלה קדמון חפץ ויכול, פועל כל הנמצאות הוא ובידו לשנותם, כפי שיחפץ בכל זמן מן הזמנים, כמו שעשה במצרים...
The mitzvah to tell about the Exodus from Egypt...Among the reasons for this mitzvah: what was written in (the mitzvah of) korban pesach.
(The mitzvah of slaughtering the pesach...Among the reasons for this Mitzvah: in order to constantly remind the Jews of the great miracles that God did for them in the Exodus from Egypt.)
One ought not wonder why many mitzvos, both positive and negative, relate to this theme, for this is a foundational principle and central pillar of our Torah and Faith...an absolute demonstration and proof of the creation of the world; that there is an eternal God who wills and is omnipotent, who created everything that exists, and can alter reality, as He willed at specific times, such as with us in Egypt...