A couple of questions before my first water fast

Hello,

I'm 22. In the last couple of years I struggled with Depression and eating disorders. I put on a lot weight because of unhealthy lifestyle and eating trash food. Anyway, recently I managed to get myself together and I would like to do a Water Fast to give my body an opportunity to clean itself and lose a few pounds.

I plan to go for 3-4 weeks. I've done my research on the issue but there are a few things that seem unclear to me and I'm curious to hear opinions of people who've already fasted:

1. Are enemas necessary?

2. I expect to feel weak for the first couple of days but does it get better later on after body switches to kethosis? Is it possible to maintain a fairly "normal" lifestyle (go to work, study...?)

3. Are there any contraindications for physical exercises?

4. How long does it take for tongue to go from white to normal after breaking the fast?

height 5'6"
weight 220 lbs
(how much weight can I expect to loose, e.g. on a 30 days fast?)

Thanks in advance for any help