Playing Video Files

Hello, maybe this is a simple one.
Maybe I just did not find the documentation.
I have installed OSMC on my RPi, configured ssh access.
After some fiddling with a black screen (somehow a MySql was configured where I do not need one),
I managed to set up my mobile as a remote control using the KORE app.
I also set up a NFS link to my Linux box.
So far, so nice.
Now I want to play video files from the linux box, *.avi / *.mp4 / *.flv - but I cannot find how to make them visible in the OSMC menu.
Where do I enter the directory path? - or the other way around, where do I put the video files, so that they become visible under which menu entry in OSMC/Kodi?
Regards, Wolf1231

Did you add them as sources?

https://kodi.wiki/view/Adding_video_sources

Thanks for the quick reply!
Actually, after I attached a keyboard to the Pi, it all went easily.
I just was horrified by filling the directory_path entry using the up-down-right-left keys on the remote - thinking “this cannot be right”.
I am done, so far.
One more question: I succeeded in modifying/removing a source, by editing sources.xml over ssh.
Is there a “better” way?
Thanks.