Agree with Steve, the bar is the place to start, but here is my other 2 cents, the one thing I wish I would have known at 18. Warm up the joints, warm up the muscle, don't jump to the 60% of max set one. Learn the form and avoid injury.
The goal should be to saturate the muscle with the creatine. The is typical easiest to do by feeding the body when most depleted. For most people that will be first thing after waking up and / or after working out. If you are taking in 4-5 grams of monohydrate per day you will be fine; HCL...
Absolutely! My wife was prescribed 2 iu daily for fertility / improved egg quality (we had twins). Now she still takes it 2 on 1 off for the regenerative benefits.