2016: Do the ios Sharepoint and OneDrive applications not work together?

I am running sharepoint on-prem 2016.

Hi all. I have a problem with mysites onedrive and the onedrive application. When I press share, I can not share with AD users as if I were on the computer. I can only share a link via email.

On the opposite side, if I use the sharepoint application, I can do everything possible, but when I set up websites as modern (and not the embedded website view), I can not see the side menu to see what is shared with me.

What am I doing wrong?

Also, if I try to share a note, I get the error that I can not share with external email addresses. I can not find anything anywhere to enable this. All I find is for online sharepoint.