What level of education do you have?
The math tends to look scary if you haven't seen it before. It isn't really that bad.
Line/plane intersection is a basic formula taught in high school algebra. I'm not sure what age that is in your country, around here that is age 16 or so mathematics. We also learned about taking barycentric coordinates in middle-school trigonometry by about age 14, although I didn't learn it under that name.
By the time you get to college studies, this is one of the early topics they review during linear algebra, which is the study of manipulating lines and coordinates in space. Linear algebra is often a second or third year college course. Linear algebra is really the basis of 3D simulations, so unless you either self-educate on the subject or reach that level of college math in school, it will likely remain beyond you until you do reach that level.