I cannot Change my activity goals. There is no “change goals” button displayed.

Figured this out (thanks for nothing apple):

You'll want to Open the Activity app on your Apple Watch. Swipe up, then press and hold the MOVE section. Weekly Summary and Change Move Goal will pop up. Click change move goal then add or subtract from there.

Hi Cindy Chesler!

It sounds like you’re trying to change your goals in Activity, and we're happy to help. You can review these instructions:

Use the Activity app on your Apple Watch

If you need further help, you should contact Apple Support using this link:

Contact Apple Support

Cheers!

This is a watchOS7 feature.