Please tell me how long it takes for to get noticeable results when starting a diet/exercise program?

It depends: On the program. The more carefully you eat, the more consistently (not vigorously) you train, the more rested you are the quicker results will begin to show. Remember, results will show more quickly for people who (1) don't have a lot of weight to lose, (2) eat healthfully , (3) and are in better general shape initially. That said, dramatic results can occur in a matter of weeks!