undecided major (common app help)

hey guys, merry christmas eve.
i heard that if you pick a major, colleges will look at your grades based on that major u chose. is that true?
also, on common app, colleges ask you to pick top 3 majors that you’d like to apply for. should i put undecided for all 3 choices, or should i put #1 as undecided and #2 and #3 as majors that im interested in

bumpity bumpity bump

It would help us to help you if you told us what colleges you are considering. There is no one-size-fits-all answer to your question.

im applying to stony brook and buffalo