First of all, this thread is full of useless advice for you. You didn't specify your height or your BF%
You CAN effectively hit all body parts in a 3 day split so that other guys advice above is false. But, I would definitely change your routine because at 160 pounds, you are definitely still a beginner and shouldn’t be doing that split yet. These splits do work… But it isn’t the best solution for you at this point since you’ll be missing out on tons of size due to your lack of volume vs. recovery. As for supplements. No to loading on creatine. Yes to taking creatine post-workout along with your Whey or isolate protein.
First, you need to calculate your 10 rep max for all compound movements for:
Deep Squats (Ass below parallel)
Flat bench press
Bent Over Rows
Stiff Legged Dead Lifts
Then, we can create a routine around those numbers. Your 10RM should be about 70% of your 1RM
If you’re looking to increase size, you need to increase strength. This is why we're working off you're 10RM. The amount of weight you gain is almost entirely dependent upon your caloric intake. At 160 pounds, your caloric maintenance levels are around 2400 calories and around 3200 calories if you need to put on some size. Focus on a % split of 40/40/20 for carbs/proteins/fats
As far as slimming down your waist/abs – I would suggest high intensity interval training for no more than 2 hours a week. HIIT is more effective than aerobic level cardio at 70%MHR IF you are trying to gain muscle (lifting weights). Otherwise, cardio for 20-30 min at 70-80%MHR will be perfect for losing body fat. Remember to keep your calories clean.