Here are my two cents:
Again, will this engine teach me how to use it?
There are currently 7 official video tutorial on engine usage. These tutorials covers the layout and scripts that comes with the engine.
How to code and all that?
There are several written tutorials as well as video tutorials. Like every programmer you have to start with the basics. Do not expect to know how to program a full game within a few days.
How do you aquire tons of textures to use for like foliage and everything like that?
Although the editor comes with some models and textures, not everything is provided for you. You can look in the assets store for free models as well as other websites on the web. The asset store is currently under revision since the Steam workshop is now active.
How do you get tree models to use and what not, that arent taken from other games and what not?
You either model them yourself, hire or team up with an artist or try to get them from a free model website like turbosquid.
I over all want to learn how to be my own game creation company. I want to make something that people will enjoy and recommend to others. Creativity has always been my passion. I play music, I play games, and most of all I love colaborating with other people. So I hope that I can find out the most I can about this engine before buying it, because I can not afford unity pro. 1500 Dollars seems quite expensive.
I can only say that you have to invest a lot of time learning and making stuff. Don't expect to much of your first games. Learn how to program by either following tutorials, editing existing scripts and a lot of trial and error. That said: follow your dreams and don't give up.