Hello I wondering how I should setup my nas to be able to easy backup my familys computers and cellphones?

Create a share and use that as the backup location for a crashplan docker available through the community apps plugin. That would be my recommendation. Just be aware of how much memory your system has as there are some java memory tweaks that can be done. You share out a code with family members and they autobackup to you.

I personally use the Reslio Docker to back up 2 of my Macs. Pick what folders on the Mac and pick the destination folder on your server and it does the comparison and syncs whatever isn't matching.