First up one week will not show any difference, you need to be going for months until you start to see any difference. Secondly in terms of diets start with protein (meats), carbs (pasta) veggies and go from there. Pastas and slow release foods like this are best fro workouts as they give you energy slowly over long periods so have soem before going to gym. You should also definitely go to a health shop and get some protein shakes/bars and also get some tips from them.
Make sure you mix up your gym routines to target different muscles and dont forget cardio, so many guys just do weights and no cardio/stretching and end up so stiff muscly they cant bend over to tie their shoe laces. Oh and get into boxing or martial arts, great for overall tone muscle defintion.
Good luck!!

I would recommend drinking protein shakes.
My brothers are football players and drink them to bulk up (along with lifting weights, etc.)

Or just get more protein in your diet through meats, etc.
Just be careful and don’t over-do it. Obviously you can’t survive on protein alone.