Welcome!
My suggestion would be to read through as many of the diet plan related threads as you have time for and then begin to think about what plan is closest to the way you want to eat for the rest of your life. While people often think of a "diet" as a specific activity (with a start, middle and end) most of those who lose weight and
keep it off are doing so by eating (and exercising) with the same (or similar) control that they had while they were losing. Check out the maintainers forum for great advice that will help you now and later.