Hi, You have roughly 80 lbs to lose. If you lose 2lbs a week it would take 40 weeks. You'd likely lose more than 2 per week for the first few weeks then it would slow down a bit. To lose one pound a week you have to eat 3500 less calories that week or 500 less a day.
If your goal is 205, then 2000 calories is about what you should be eating. Don't get discouraged that it may take awhile. Try looking at if you DIDN'T do it. You'd still be the same in 40 weeks. By Christmas you could be nearly there and ask Santa for all new clothes
Good luck to you.