Well here's my no shiv explanation:
You have about 25% bodyfat. You start an exercise program right now you'll simply end up looking proportionately like you do now, just smaller.
If you want 'teh abz' or whatever, you need to gain weight to put on more muscle mass. There's no definition because you have no muscle. Eat 3000 calories a day at 5-8 meals a day. No processed junk, cut your sugar out, stop drinking beer, don't drink pop, no candy. Make one meal a week a cheat meal where you indulge.
Eat an asswad of protein. Eat only whole wheat products. Get your fats from natural peanut butter and milk. Get to 185-190#, accept the fact you will no longer fit into any of your clothes. Then drop your carbs completely, cut your calories back to 2500.
Start lifting weights, stop running unless you're going to do HIIT. Squat, bench and deadlift. Three sets of five, alternating days (MWF, TThS, whatever) Don't do curls, they are a waste of time, don't do sit-ups because they are more than a waste of time.
Workout A: Squat, Bench, Deadlift
Workout B: Squat, Military Press, Clean
Week one: ABA
Week two: BAB
Week three: ABA
etc.
Gaining weight will take 3-4 months, shedding excess body fat will take about 2-3 extra. To stay that way, you need to maintain caloric intake.
Size comes in the kitchen, strength comes from the gym.