とでも思ってる

do you think ... or something?

→ と
phrase Rare #39,866
do you think ... or something? Used in rhetorical questions, often expressing disbelief, criticism, or irritation. It follows a statement or noun and implies that the speaker thinks the idea is absurd or insulting.
JA: 私が何でも言うことを聞くとでも思ってるの?
EN: Do you think I'll do whatever you say or something?

オモチャとでも思ってるのか

Do you think I'm some kind of toy?

— RRR (2022)

本気で私がお兄ちゃんを殺したとでも思ってる

Do you seriously think I killed my brother?

神さまとでも思ってるのよ

They think I'm some kind of god or something.

— ロシアン・ブラザー (1997)

おれが仕組んだとでも思ってるのか

Do you think I set this up?

— レザボア・ドッグス (1992)