Different aspect ratios on phone/computer (mac)

[Ousimanie]

I saw a post about this 3 years ago but it was for Linux. I got started with scrcpy just today and have only been copy-pasting commands in terminal; forgive me if my knowledge is lacking.

I'd like to use my phone as a sort of mini-tablet, mostly for my studies. I have a galaxy note 10+ so I want to use the s pen in conjunction with a mirrored screen on my macbook air. Scrcpy copies the aspect ratio of the phone however, and I end up with black borders on the top and bottom. Can you make scrcpy fill the screen? Or is it always tied to the phone's aspect ratio?