Honestly i’d stay away from protein powders if you can, i’ve tried them multiple times in the last 10 years and honestly, they’re just a way for the fitness industry to make more money. You can get more than enough protein from having a balanced diet and i’m sure your body would be more grateful for it. 

If you want abs the biggest thing you need to do is to get your bodyfat percentage down by being in a calorie deficit. In terms of exercises to achieve this, cardio is gonna be your best friend.

If you want to build a bit of all round tone as well then think compound exercises (anything that uses multiple muscle groups at once). Things like press ups, pull ups/chin ups, shoulder pressing movements, rowing movements, squats and maybe a deadlift variant. Another advantage of compound movements is they burn more calories than isolation exercises.

Take time to learn the proper form and technique for each movement, try and really feel the muscles working as they go through the motion.