How do I get rid of ads struck on bottom of games

if you subscribe to apple arcade and only get games from apps store arcade section then there will be no adds

otherwise it may not be possible at all, some game developers have 2 versions one with adds that is free and a paid one which does not have adds

if it was me then I would check if that is the case for the game you play and maybe reach out to the game developer

How to contact an app developer - Apple Support

To get rid of ads in apple arcade:

1. Go to Settings > Privacy & Security* > Apple Advertising.
2. Turn off Personalized Ads.

Thanks