Not much video tutorials as video isn't very helpful. It is entertaining as videos are, but do little to actually get you to code anything.
The only real way to learn is to actually do, to trail and error your way through issues.
I can however recommend you search youtube, I have found a few good videos there.
And this could be what you need to look at as it offers the basics in a visual way.
If you could rephrase your question might help to, as I don't understand exactly what you mean.
I can tell you that the manual is probably the best source of information.
For example here is a list of expressions without the math. Just the forumala's if you will.