It depends what software you have , all of the best ones to a newcomer are frightening in their complexity and cost ie they take ages to learn, and thats just imaging things, 3d is a lot more advanced.
To do 3d landscapes youll have to either get a free programme or an expensive one, try a free one first and see what it can do, be warned though it'll take a while to learn.
You could try and publish a few textures and see what happens people always like them , the more unusual the better.
They have to be flat, no shadows or uneven light, in focus res 1024 square and tiling though usually. just decent pics of unusual things might be OK tho, just have a general look around this site and formulate a plan.
Have a look at my stuff to see textures star ratings downloads etc to get some idea.
And yes you can simulate things in a programme v realistically, but it has to be good and usually involves a LOT OF WORK.
The world standard for image manipulation is photoshop, its easily the best thing ever.
photoshop elements is pretty good if you havent money for photoshop.
You'll need some other person to help with 3d.
PS and good to see you around Frendo.
That model is good most cgi models I've seen have a prob with eyes, they're cross eyed.
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