Allowing Player To use pen

Hi! So I'm doing a school coding project and I need help with knowing how to have the player at a certain scene be able to use a pen that is controlled by their mouse. For more details I have a cross word puzzle and I want them to be able to circle the words with their pen. Im also wondering if there's a way if the person messes up with the pen that they can revert their mistakes and let them start again.

Edit: So I was wondering when the player is using the pen and makes a mistake they can revert their last move with the pen instead of reverting everything by using the "Clear" Code in pen.

Hi and welcome!

Sounds like a fun project. I guess you want a sprite to have a pen costume, and then use the WHEN I AM CLICKED block (which has other options besides "clicked") to draw on the stage.

I'm not sure if that's too much or too little help. Have you used more than one sprite in a project before, for example?