In your cloud sync app, you should be able to ask it to sync your camera folder - I know the nextcloud app asks if you want this, and you can also point it to specific folders to keep in sync.
If your self host cloud doesn't have an app, just use https://play.google.com/store/apps/details?id=dk.tacit.android.foldersync.full to sync chosen folders.
No judgement on what you're doing online. In your case, don't download untrusted files, stream where you can. For all users, whether on the black seas or not, you should as a matter of habit use uBlock Origin in your browser, turn on the filterlists for security, ads, annoyances in particular.