[Plugin: BulletProof Security] Renaming admin.php

BPS does not attempt to do any hiding of things as this is a completely ineffective security method.
If you mean obfuscation in the true meaning/definition of the word “to make obscure”. Then these are the things that will obfuscate your login.

1. create a username that is obfuscated – X72PllQY33
2. create a very secure obfuscated password
3. make sure that your publicly displayed author name is not the same as your login username.

And of course you want to install a login protection plugin that will let you limit login attempts and lock out multiple failed login attempts.