İPad and Linux Nextcloud sync problem

Hello, I want to sync Logseq from iPad and Linux, there is Nextcloud option but I can’t open or move the safe from there, it’s sealed, what’s the reason?

As far as I know you can’t use on iPad any other app than Logseq sync. Every app has its “work folder” and you can’t acces from outside.
Yes, you cant use a git client or any “shell” software, but It’s a bit complicated for begginers (like me).

Hope it helps.