Really confused on how I should bulk.

A little background: I'm a 16 year old who fairly recently started lifting (right at the start of February/end of January), I'm 5'9 and 157 lbs. I finished my cut a month ago and I've been bulking at 250 surplus since then, and steadily gaining weight. My question is, am I optimizing muscle gain while minimizing fat gain? I'm doing a slow bulk because I want to minimize fat gains, but I've read conflicting things on what amount of a surplus I should bulk at. Since I'm going to be slow bulking until March, I don't want to gain too fast.