amazon purchases - 3% cash back?

3% is only for purchases directly from Apple and a few other merchants. 2% from others if they accept Apple Pay and 1% if they don't.

Amazon is in the 1% category. Also see: https://apply.applecard.apple/?cid=apy-310-100000070000-100000000000876&utm_content=realdailycash&utm_vendorid=100000070000&utm_searchgroup=br_noncore&utm_cmpid=19716425460&utm_adgid=144698296245&utm_adid=648945623713&utm_tgtid=kwd-812028171810

You’re not clear on what you are asking. Using the Apple Card with Apple Pay you normally only get 3% cash back when purchasing Apple products and services. Otherwise it’s 1% unless there’s special promotion going on. If you are using another credit card with Apple Pay that credit card company determines if/what cash back options you receive.

Purchases from Amazon would be 1% unless there’s some kind of promotion.