Foods that have protein, eggs, red meat, peanut butter, almond butter
2% or whole milk, chocolate milk,
Or, you can try a protein powder, such as Whey, can buy a Wal-Mart in like four flavors. Good luck!
Im not very informed, but how are your test levels? I am assuming you are taking steroids still? Im not sure how your body is coping but my first thought would be to elevate your levels, because i would feel like it would be hard to really gain for you.
If your trying to bulk up your going to need to give more info for a proper response. Your thin in your picture, do you have a high metabolism? How often do you train, what does your current diet consist of, what's your height, current weight, what your ideal weight would be and remember muscle is much denser than fat?