YouTube Color Balancing

So this is really hard to describe, the best way I can do so is with this example: So you know when you’re watching videos on a computer monitor and if you look from a sharp angle (say directly to the side of the computer) the video gets a lot of shadows and becomes mostly black (I feel like I’m doing a terrible job of describing this) but that’s what my YouTube videos look like the majority of the time. During dark scenes specifically. Help would be much appreciated.