how would i make a check box to make it windowed or not?

Exactly what the title says.

I have all ready made my check box, which is a GUI Texture of a tick box so when you click on it the box then has no tick on it
( I’m On 10 years old and not learned all of java code yet!)

How would I make that check box so when it is checked it will be be a windowed screen, but when it isn’t, it is full screen.

When they check the box use:

Screen.fullScreen = false;

And set it to true when you don’t want windowed mode.