How to trash emails from 1 sender

To trash a specific email address:

Use the search box at top. Pull down to show search box. Write in specific email address.

At top click on edit. Click on select all and at bottom click on trash.

A box at the bottom will come up to verify: delete all?

Then delete in trash.

To block a specific email address is different.

Ask for help with the Apple Support App. They are very helpful.