Connections to host on the default ports failed.
How do I fix this email problem?? Help please.
[Personal Information Edited by Moderator]
The google account and second one in your screen shot are offline they should be always online see the article https://support.apple.com/en-in/guide/mail/mlhlp1032/mac
And then just click the desired one say google ( online ) - try with selected server the mail compose window opens , you can fill be the credentials and send mail .
If you can’t take an account online, make sure you’re connected to the internet. If a warning icon 
appears next to the account name, click it to open Connection Doctor. Learn more about using Connection Doctor.