adding an email address to my account

I have two questions:

1. I just installed defender plugin, among other security plugins, I would like to receive all messages to my new alias address address.

It goes to the same gmail account, however I want to configure it as urgent messaages, but the plugin states that it does not recognize this address as admin address.

Is there a way to update the address?

2. I would like to block login attempts by user (for example, admin or other non-exixting users, is that possible?