Well, I won't do your essay for you, but I can help outline some stuff you can change which will improve your health. Then, I'll leave it to you to explain how it does so! =)
So, I can't say these specifically apply to you, so I'll just make some generalised changes you can make.
* begin working out
* eat healthier and nutritious food
* begin meditating
* cut out addictive tendencies (video games, etc)
* learn to love yourself (loving yourself is a key to confidence and self-forgiveness, which leads to better mental health)
* work on proper and consistent hygiene
Hopefully, this helps! =)