Screen keeps shutting off, backlight/brightness issue?

I'm no computer expert, so i'll try to make this concise.

My Macbook is about 6 years old, and recently I was using it and suddenly the screen shut off, went black. Thought it was out of power, so I charged it but still nothing. Restarted it, and it came on and then the screen flickered off again.

I thought it was dying. But then I noticed that I could just faintly see some of the background of my computer. Then I realized I could use the computer when this happened by turning the brightness all the way off, and then turning it back up, at which point I could see the screen and use it fine.

However, this happens somewhat frequently, where the screen goes dark. From my searching it looks like it might be a backlight issue? However i'm not confident about fixing it myself, though if desperate I would try. Is it an expensive fix?

Any tips/advice would be much appreciated. Sorry for long post, felt like the issue required some description. Thanks in advance tho!