I do wish to avoid GAFAM as much as possible and degoogle my android. Now, all the apps are not available on f-droid. APK Pure and APK Mirror do have those apps, but they’re not getting installed into my device after downloading. What could be the reason ?


The amount of repos available to add to F-Droid makes the app selection pretty deep in my experience. Here’s a few:
Izzy Droid - https://apt.izzysoft.de/fdroid/repo
Guardian Project - https://guardianproject.info/fdroid/repo
Ironfox - https://fdroid.ironfoxoss.org/fdroid/repo
Futo - https://app.futo.org/fdroid/repo
Fedilab - https://fdroid.fedilab.app/repo
Molly - https://molly.im/fdroid/repo
Briar - https://briarproject.org/fdroid/repo
Anonymous - https://anonymous.gratis/fdroid/repo
There’s a bunch more repos you can find online, but I’ve always enjoyed having these enabled. Additionally, there’s the Aurora Store from F-Droid, which allows anonymous access to the Play Store. There’s also Obtainium, which will directly access developer’s GitHub/GitLab/Codeberg/SourceHut repos as well.
Does aurora support split apk yet?
Last I checked it was impossible to install basically any app due to that.
I find the apps from playstore extremely bloated.
Good list, but you missed the most important one: https://idlefantasy.tristinbaker.xyz/fdroid/repo