As one of the new features of the MS Teams that Twitter runs over with, is that we can have Guest user access in Teams.
Well to add a user is real easy, but there is some limitation about it.
As this shows you where I tries to add a guest user to one of my Teams
Then we get this message
Your account has to be O365 business or school account.
If it's one of them well then there is no problem to get this new feature running.