I found videos online that explain dot product and cross product

You can look for more interesting videos on this channel about mathematics.
Dot product video.
Cross product video.

Yes, I love those 3Blue1Brown videos! They are absolutely worth watching, if you’re interested in a deeper, geometric view of many topics and how they fit with other areas of mathematics. Those videos, in particular, show how the dot and cross products connect with linear algebra.

Those videos tend to be a deeper than necessary, though, when you’re trying to get the basics. They’re a bit sparse on computations, for example. If you really want videos that explain this stuff from a bit more fundamental level, I think it’s hard to beat the Kahn Academy videos. Here’s their cross product video, for example: