Not to try putting you off or saying your not capable but what your proposing at the size your proposing is very ambitous for a first build.!! . . . .Be very truthful with your self regards your abilty's and don't be afraid to ask for advise or help if at all unsure.

After some research and when you feel you have a handle on what you want then Be patient don't rushout and buy stuff before running it by us because it's very easy to get wrong stuff.
At the same time and contry to above "Be patient" advise Don't get to hung up on drawing stuff to the last degree just the basic design layout to check fitments etc and materials to used is all you really need then get stuck into building. Often doing too much research can have a negative affect and fry your noodle.
Often you'll see people take months or years on design never to see it come to fruision and if it does it rarely resembles the paper design when finished.!!

Good luck, if done correctly and patiently then it's a very rewarding journey.!