I'm looking to set up 3 e-mail accounts or users for my children and their new ipads
Okay, but what is your question?
Do you wanna know how to add those email accounts? Should be this case, start here:--> Add an email account to your iPhone, iPad, or iPod touch - Apple Support, bearing in mind that if your children iPad are running iPadOS 13 or earlier, the correct path to use is Settings>Passwords&Accounts>Accounts.
If you mean something different, please better specify your needs.
Regards
Giulio