How to use constants.statusBarHeight ?

Hi everyone I’m new to expo and programing in general, and I wanted to ask for help because I didn’t understand the concept of the constants.statusBarHeight and I don’t know where to begin.

I need to use it because my linear Gradient background doesn’t wanna cover the entire screen so I used margins and height but I know that it would look bad for different phones.

Please someone help I’m desperate :frowning: