Leaving iCloud. So many questions.

Hello everyone. Delete if it’s out of scope on this sub, but I think you guys would be the best to answer my questions. I’m projecting to migrate from iCloud to somewhere else but I’m still questioning myself about the destination. Indeed, I am a pretty much « everything that’s important goes in iCloud so I’m not worried about the security of the data ». iCloud is encrypted, 200 Gib for 3€, that’s ok for me. But the thing is, iCloud seems to not be accessible through Android, and I do not want anymore to be