57, male needs some support

I started at 243lbs last sunday and I think that this site is going to allow me to lose the 25lbs that i have been carrying for the last 10 years. I figured that if i start with a reasonable goal of 25lbs I would be more likely to attain it than trying to go for the 43 lbs I really should lose. One step at a time I feel. The site has been telling me that if I keep my caloric intake at the level they suggested around 1650 per day I should get near that target in around 3 months with a 2 lb per week goal Has anyone else had that kind of success? If anyone has any suggestions regarding intake of water would be appreciated. I have 2 glasses of water during the day at work and then switch to seltzer at home at night, but 8 glasses is a lot of water. Any insight would be appreciated. Any buddies out there a friend would be helpful as well.