If you're expecting anything remotely like an Android experience on Apple's devices, you're going to have a horrible time. Anything even vaguely resembling your own file system, or non-Apple browsing engine, or alternative app store is basically nonexistent. And the way Apple squeezes indie developers means you've got less choice between decent apps even if you look on their store.
Among other missing apps, you get no Syncthing, no Firefox, no Tor Browser, nothing remotely like F-Droid or Obtainium...
... And as far as I can tell, there's no such thing as an alternative to the Apple App Store (which mandates an identity and a signin), which isn't also run by Apple...