Hi Llama1994,
You are off on a good start with your project, and that’s great! The question that you selected about the healthier diet is an interesting one so now you need to follow the steps on the Science Buddies Science Fair Project Guide page to continue.
A good idea is to look at the Science Buddies section on following the Scientific Method, at
https://www.sciencebuddies.org/science- ... thod.shtml.
The information there can help you decide what data you should include on the display board.