First you discover F-Droid and Aurora, and then you discover Obtanium and install everything directly from github!
I second this message. Go to https://f-droid.org/ ...to download the f-droid apk manually. Install that. Then while f-droid has SOME FOSS apps you might use (like organic maps), definitely use it to get the Aurora Store and Obtainium. Aurora Store will get you normie app store things like Fountain.fm (free sats for listening to podcasts). After you get used to Obtainium, it will be your go to. Can retrieve app apk's and manage updates (at your discretion) from F-droid and/or Github etc.