Signed up with Gmail account

Hi there i signed out all the ZOHO apps with a gmail account this I think it was my first mistake.
Anyways i was successful setting up my own domain email. Now my user name and atlas is my domain email.

So are they officially linked?
Does my domain e-mail have a password? or is just linked to my original gmail account that i signed up with ?
Is it possible for me to use my domain e-mail now created to access all my zoho apps?

I would just like to separate these two email accounts
Please advice
Thanks!