How do I fix blank Email Screen on iPad?

Your footer shows an iPhone, with no mention which iPad or iOS / iPadOS version, so I can’t tailor this reply to your particular iPad and iOS / iPadOS.

Back up your iPad.

How to back up your iPhone, iPad, and iPod touch - Apple Support

Update to current iOS or iPadOS, if not already.

Try a forced-restart:

If your iPad won't turn on or is frozen - Apple Support

Failing that forced restart, remove the mail accounts in Settings, then (if your iPad is new enough) remove the Mail app, force-restart iPad, reload Mail app, and re-add mail accounts:

Delete built-in Apple apps from your iPhone, iPad, or Apple Watch - Apple Support