Hey there, 20Ollie14!
Thanks for reaching out in Apple Support Communities! If we understand correctly, your iPad screen only becomes unresponsive when connecting with your charger. We understand how this can cause a less than pleasant experience and we'd like to help!
Since this happens when connecting to a charger, we'd like to see if you can try connecting using a different outlet, cable, or charger.
Should this persist, continue using the guidance in the following support article:
If the screen isn’t working on your iPhone or iPad - Apple Support
"If part of your screen doesn't respond, responds intermittently, or responds even when it's not touched, contact Apple Support for your iPhone or iPad."
Take care!