What is the best way to stop screen flickering/fix screen issues on a Mac?

I started having issues all of a sudden with my screen-a bunch of random colors and black are blocking the left side of the screen horizontally, and there is flickering on the bottom of the screen. Now there is flickering in general and then I will be working, and then the screen will almost disappear into areas with lines to where I can't see what I'm doing. Sometimes restarting or turning off works for a while and sometimes it doesn't. The MAC(MacBook Pro 13''and the year on it is 2015) is fully updated with the current Big Sur. I did read about this issue, and clearing up cache was suggested for this problem(I was able to see an exact replica of my problem) But I don't want to download any software in order to fix the issue just because someone suggests it. This article did also suggest a NVRAM restart and a few other things. I just wanted to get some thoughts before I decide to take it in to the Apple store.

Thanks!