Using another iCloud e-mail with another Apple ID
I have 2 Apple IDs:
1) my main account used for my iPhone / iPad / Mac - it has all my backups and all my media purchases associated with it
2) another apple id that has my iCloud e-mail / calendar that I use.
I want to be able to use my iCloud e-mail account / calendar (account 2) on all my apple devices which i currently use AppleID 1 to log in to. What is the best option ?
Am I able to move my iCloud e-mail from 2 to 1 ? or do I have to transfer all my subscriptions / backups / etc.. to 2 and use 2 to login to my devices so that I can simply use my iCloud e-mail on my devices
(I don't want to use another e-mail / calendar tool as they lack the integrations i want that come with having the iCloud e-mail associated with my account)