Account and Email and Password

Account and Email and Password

I'm signing up as a Partner so I can move my website clients across to a separate email server from their current cPanel one..

So I have a Zoho account and then I moved one of my emails across to that account to test the import process... 

So the question .. is my email password the same as my Zoho account password.  I can access my emails on Trident and via a Browser but it fails on Apple Mail..  There is 2FA set up on the Zoho account so do I need an App specific password...  and will all my clients need different Application passwords for each of their devices they use to access their emails?

TIA

Pete