The most straightforward answer is: eat the foods that you enjoy! We can list out tons of healthy food options, but it really all boils down to the foods you'll actually like to eat.
We recommend going through the different food groups, finding healthier options, and sticking to those foods. The food groups primarily consist of fruits, vegetables, grains, protein, and dairy. Almost all fruits and veggies are excellent options (within reason, of course – we would never recommend doing something crazy like a broccoli-only diet).
When possible, pick foods that are whole and raw over juiced, dried, or cooked. Healthy lean protein sources besides your protein powder include eggs or egg whites, tofu, beans, and lean meats such as chicken, turkey, and lean cuts of red meat. Prepare your proteins with little or no added oils/fat, and choose boneless and skinless cuts. For grains, choose whole grains such as brown rice, wheat pasta or bread, whole grain cereals, popcorn, oats, and quinoa. For dairy, choose 1% or fat free, as these options provide the same amount of protein and other great nutrients, while being lower in saturated fat and calories.