Basically it's high in protein but low in carb.
Chicken Breast, delicious and easy to cook. High in protein and cheap too. Everyone if training or not should eat this often.
Suggestion: Grab some spice and hot sauce so it won't taste the same everytime.
A burger, yes. It's basically a nice meal because you can eat veggies, a nice piece of meat and bread at the same time. The problem with burgers is that basically the shit you get a Mc Donalds won't satisfy your body with things it needs for a proper nutrition.
Suggestion: Grab some nice beef burgerpattys, beef is high in protein.
Oats, the mother of proper diet. Oats are high in fibers and provide much protein, also they are able to be combinated in many ways. Look for some recipes on the internet, or just eat them raw with milk.
Suggestion: If you want to flavor your oats use flavored proteinpowder.
Suggestion: If you can't the taste of cottage cheese, try to sweaten it (Honey) or to spice it up (Pepper).
I would also suggest supplements, for example Fish Oil Capsules, they contain a load of Omega-3 which can only be found in fish. It's a cheap alternative to eating fish. I would not suggest medicine, or steroids. If you think you progress too slowly maybe, but in the first 2 years, stay natural. It's the best thing you can do for your body.