Can you explain in very simple terms how this is done?
What I mean is a step by step guide through every single step of the process, i.e. where you go, what you click on?
If you are a bit confused from the suggestions above why not follow some guides that are already on youtube?
I found one video which is easy to follow when verifying Electrum and its signature.
Check this one
https://www.youtube.com/watch?v=TzOHLL_dKCMJust make sure to change the version when typing the command you don't need to open Kleopatra according to the guide above it is pure command prompt in Windows.