Which one? You can check officially supported here: https://wiki.lineageos.org/devices/#samsung But it is possible that yours is unofficially supported. In this case you have to read xda forums.

For links, I use Pocket (you can use Wallabag, but I find the interface not efficient at all). For files, you can sync a folder with syncthing (but you only switch it on when you want a quick sync, otherwise keep it off for battery). If you just want to put some file on your phone, install FTP server (free) from F-droid and switch it on when you need it (there’s even an optional switch on quick actions). Use Filezilla or any file browser (if on Linux) to exchange your files. Remember to switch the server off once finished, because FTP is not a secure protocol.

Install LineageOS or e/os/ on your phone and bye bye Gemini 🙂