HI, my mail will not open up. can anyone help?

Have you tried the instructions on this page: If you can’t open Mail on your Mac - Apple Support?

Follow instructions from@ Pactricia666.

If still not luck >> Launchpad >> Other >> Activity Monitor >> View >> ALL Processes and verify of Mail is active or not. If active, Force Quit. If not active, Applications folder >> Keyboard key Control and Click Mail - popup appears and choose Open.