A nice open source app in F-Droid is called Droidify:
It makes adding repositories easy. Tap 3 dots in upper right corner and pick repositories. Tap the ones u like. I have these selected:
Brave Browser, Breezy Weather, Briar Project Repo, F-Droid, Fedilab Apps, Guardian Project, IronFox OSS, IzzyOnDroid F-Droid Repo, and Session F-Droid.