❔ Prefab different sizes on 2 different monitors.

I'm working across 2 different computers with 2 different monitor resolutions. I have a prefab which is the right size on one monitor, but too small on the other. How can I get them to be the same size on both.
I notice the game over text has a canvas scaler which has a 'scale with screen'option. Do I need to incorporate something like that? Thanks