hey guys my group has decided to make a fitness app for our software project but we are unsure about who the target audience who do you guys think should be the target audience for using this app???

I am age 57, mentally disabled just looking to answer and ask questions, I live on the East Coast of the United States of America I try to give positive advice and keep things for real and I expect the same treatment in return have a Blessed day hope God Blesses your day with the best of health, happiness, Many Blessings.