Passwords

I am trying to understand/resolve password problems . I have an account which uses 2 different emails, one is VM and the other Ntl. Also 2 O2 phones are linked to the account.

when I open my VM using my virginmedia02ID and go to manages linked accounts, it does not show both email accounts and one of the phones

How do I add the missing details to that account or do I have to set up another virgin media O2 ID for the missing email account. This would mean I have to set up yet another Gmail type account just to access all the virgin media household accounts.

Also, can you confirm that I will only ever need

1. my virginmedia02 ID and password to access my virgin media account and emails
2. My virgin media recovery password with format word-word etc to use with outlook and apple mail( including setting up account details for mail on iPad/iphone. That all other old types passwords will no longer work. 

I’m also concerned that I if I use the latest recovery code to set something new up , I will have to reset  all the accounts previously set up with the old recovery code . I need to know in advance so I can act on it .

it has taken me a long time of talking to phone help and looking at past information to ask these questions. I am not familiar with a lot of IT and have found this whole process confusing . Finding how to change passwords is a minefield and some of the pages you are told to visit no longer exist.