Definitely get your squad down to a bare minimum. if you have 4 players more than you really need and their salary is on average 2500/wk, that's 10K a week going down the drain. And for a noobie, you want to really watch your finances to get your team going so you can buy decent trainees/players and expand your arena when necessary.
probably don't invest anything in the draft too at this stage so you can improve your finances.
As for your new player, the good thing is that he is 19 with good potential. The problem is that he is a bit too tall to quickly be trained as a guard (203 cm) and he is a bit short and has poor big man skills (inside shot, rebounding, inside def) to be trained as a PF or centre or possible SF.
He has OK guard skills so you should be training him as PG or SG. Considering his age at 19 and his height, train him i outside def to start as it takes the longest and if you train pressure (PG), he will pop quickly. Do one position training in my opinion to get his skills moving. But it all depends on how many other possible guards you can train in your lineup.