Help with workout plan

I know this will need a long reply but please help me.i am 15 and body fat percentage is about 16%.some guys in my year are ripped and i want to improve my body.i can dedicate 30 mins to cardio every day and 45 mins to anything else.i am tryin to get my parents to pay for a gym membership and i can go 4/5 times a week.i dont understand the workout routines on this site and want someone to give me a simple set of workouts to do (bench press x10/sit ups x20x3).my goal is to see abs in the next few months by burning belly fat while at the same time making noticeable progress on my arms and chest in a few months.i only have a two pack when tensing and would like to see a 4 pack as soon as i can.also what are examples of core exercices and how do they help? Thanks very much if someone gives an answer i think i can commit to i will 100% commit to it and maybe post pictures to show you my progress.thanks