You don't have to be on a diet to get to a healthier state of being. you just need to eat the right foods and get a lot of exercise.
Take a walk in the park.
Go for a run.
Ride a bike.
Take a hike.
Take a walk in the park.
Go for a run.
Ride a bike.
Take a hike.
You don't have to be out in the wilderness to go hiking, you just have to go for a walk in your park or on a walk in the city. You could even bike around your city. You should find something that you like to do around your city or close to it.