I hope you didn't delete them using an SQL query as there are numerous tables linked to the users that you have now caused some issues with. It's not recommended to delete directly via the DB unless you modify all associated tables.
In other words, you aren't sure if you modified all associated tables.
I'd suggest restoring from a backup (you DO have one before you manually modified the tables I hope) and then follow the process that Brogan outlined.
And your "translation" of "Select All" is incorrect - or you are using the wrong wording for it.
It should look like this
That's just the List All users page though. It isn't designed to do anything but list users so you can then look at the list or do things to indivudual users. Do do things to multiple users, that's what the Batch Update Users is for.
...never modify the database like this, unless you really know exactly what you are doing.
I did several SQL processes when I was transitioning from DNN to XF but those were all well vetted and tested. What you are doing has the potential to seriously mess things up, which is why the Batch Update process exists on the front end (to do it right, automatically)