if you just started lifting then you can gain some lean muscle mass through your workouts (while you are trying to drop you're body fat percentage). However if you have been lifting for a little longer you need to go through cut and bulk cycles to gain some muscle then shed the fat. Probably a 6 week cut 2 week bulk.
As far as diet basic tips I can give u is have most of ur carbs in the morning, and then some carbs after ur workout. Protein shake in the morning and post workout. Avoid fast food, frozen food, too much sodium, sugar, etc. And try to avoid carbs after about 5 Eat lots of veggies, chicken, tuna, fish, all that good stuff. Cottage cheese and milk before bed is a good source of slow digesting protein.
If you're looking for a 6 pack then cardio and dieting is the way to go. Check out forums on HIIT (sprint 1 min, walk 1 min for about 15-20 min) and do that like 3x a week.
goodluck | 
