Expanding the background

Hey, while making my game I decided that I want to change the background throughout the scenes. For example in the Title Screen I wanted that background to fill the entire screen but inside buildings it would be smaller. How do I change the size of the background?

Can you explain it more clearly?
Or if you want to change the WIDTH of the scene/screen, you can use this event
image
or this
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Though number 2 wouldn’t work, I think (never used number 2, so idk)