php – Administrator username and password

I use the security connector that protects my site from backing up malicious attacks, etc.

I checked today and there were more than 20 lockouts. I checked the IP addresses and there were no circumscriptions, they were from all over the world.

The only thing they had in common was the username they entered, that is, one of my administrator user names.

I was wondering
A) how did you get it … I suppose that from the updated page, etc., do you have any way of finding it from the source of inspection?

B) How to avoid that the user names of administration are of public knowledge?

Also, is there any way to separate the front end of the rear end, so that if they register, they can not access the rear end and make changes?

Any help would be incredible 🙂