Q: my mac will not send or receive email's... its not internet connection... my iPhone still receives emails... so I'm not sure how to troubleshoot this problem, any ideas?

If you can’t send or receive email on your Mac - Apple Support

What exactly happens when you try to send a message?

How many accounts have this problem?

Do any account work?

What specific accounts are they?

What does the Mail Connection Doctor return?

The link in my first replay included :

If you still can’t send or receive email

Mail Connection Doctor may be able to tell you more about the issue.

Id it work before on the Mac?

Can you access the Gmail account via webmail on the Mac?

All I can think of is to delete the accounts from Mac and reenter the settings.

Follow the instructions in the link