I started taking creatine when I was about 16 years old and it was purchased by my football coach and sold to all the players. You just need to do as much research as possible, because creatine isn't like taking too much protein. Your body produces creatine on it's own and you get creatine from consuming some foods such as steak, but taking creatine supplements is un-natural, so your body may stop producing it if you take too much. Most supplements have you taking 2-3 times what is natural. Most people advise to take it only one month on and one month off.
You should follow the instructions on the creatine and it's best to take it with something like grapejuice if possible. You don't have to take it before or after workouts. You can take it in the morning and at night.
Even though I took creatine when I was 16 years old if my son told me he's thinking about taking creatine I would be a little nervous. I would at least advise to take the supplement as the bottle describes and not over take it. There are reports about kidney and liver issues, but they may only be rumors. It's been used in Germany since the early 1980's, so by no means is this a new product.
I would start reading everything on wikipedia and anything else you can read to make sure you doing everything safe. Talk to your doctor as well
https://en.wikipedia.org/wiki/Creatine