How to lose weight an keep weight off

I work out ver doo actually!
But I been admitted in to hospital and my doctor takes me to the hospital gym how do I do it?
Like lose weight and keep the weight offf as it making me really depressed as I dont eat anything and I drink loads but am still...

gaining weight please help me !!!

proper diet and exercise

you might not need to lose weight. The idea is to become more confident in yourself and to know that you are healthy, you are alive, and you have friends and people who care about you. When it comes right down to it, it's always better to aim to be healthier than to try and be thinner.
Incorporate fun exercise and just give yourself a more active life. If you have been going to a gym for a while it's time to change it up a little bit. Bike rides, going out with friends more often. Don't limit yourself to your house! You have the whole world out there waiting for you! Your life doesn't hardly have to revolve around weight loss anyways. It could become an adventure too.
My point is to think of the most random ways to loose weight, the most fun you can think of. Let me think of one...
Get one of those things that counts how many steps you take, and try to reach 20,000 steps one day. Exactly 20,000, no more either :D