Yes, some foods create more muscle mass while others can create more fat. Proteins and good fats usually help with building muscle and metabolism, but don’t eliminate carbs since they are necessary for energy.
Whey products and cottage cheese are excellent sources of protein for building good muscle, plus there are fats and carbs in dairy. Many protein powders are good for building muscle. Research online or go to nutrition/vitamin store.
The sodas are probably a good idea to save for a picnic every three months. Try making your own drinks: iced teas with honey or a safe sweetener, herbal teas, electrolyte drink (One quart water, one quarter teaspoon of salt, one quarter teaspoon of baking soda add lemon, or real fruit juice)
The junk food should probably be rationed better; try to find “junk” food with ingredients that are simpler, like popcorn (try to make the real stuff with olive oil, not the microwave kind. Melt cheese on it when it’s done.) Many stores have healthier versions of junk food. Just practice reading labels. This is a generality, but the less ingredients, and the more you recognize the ingredient, the better for you.
In general it is better to do mild exercise regularly than it is to do big workouts. A walk for 30 minutes, alternating days with biking, dancing, or swimming is best. Take a day off but try to avoid taking two days off in a row. The body likes a routine. Make it fun, easy, meaningful rather than complicated and unpleasant. That will make it easier for you to stay with the program. Everyone is different so read, ask, and look around.