Send your SAT score. It’s the better of the two. Your ACT adds no benefit to any application you send.
It sounds like you are currently a HS junior. I’m going to give you some free advice. Even kids with perfect SAT or ACT scores and perfect GPAs get rejected from the Ivies every year. There simply aren’t enough seats to accommodate all of the excellent folks who apply. So…I would urge you to research other less selective and affordable colleges that you would be happy to attend.
Actually…find one or two sure things for admission and affordability first…that you like. Get that pinned down first. Bonus if it has rolling admissions or EA so you could have an early acceptance.
Then build your list UP from there. It’s easy to identify those reaches where more than 90% of applicants do not get accepted.
I am linking an older thread, but it rings true even now. Get that sure thing…or your senior year could be like this kid’s (who was a NMF, class val, excellent ECs, etc). Who didn’t get accepted anywhere the year he was a HS senior. Read the whole thread.