Currently mailcow is used in the Email Node by default in your Private Cyberspace (assuming you are an average home user).
Your application integrator should have your Email Node set up with usable defaults, so you should NOT need to touch it unless you are not satisfy with the result.
Cloud Services can send legitimate incoming emails to junk or spam email folders.vSome of the following tricks might help in whitelisting those emails.
Add the FROM email address into your address book to indicate that you know about the sender.