You need a material created; Drag & drop that material in the little material square on TOP of your UI. Then using right click you create an AREA of terrain of the set materials. Left click deletes it, take care.
Yes there is. In the material editor, somewhere down on the left there's some UV scale option. Quite a dark world you have there.
If I may suggest, stop working on your project for a while; create a test project and just play around hitting random buttons like an idiot to see what happens. That's the way I learned things. And probably most of us did. (I don't mind answering your questions, i'm just saying it might be faster for you)