In most versions of RM, how many DP a character has depends upon their Development Stats (Con, Ag, Re, Me, and SD). At first level they will basically get them twice; once for their adolescent development and the other for level 1. After that, you only get the total once per level, though that total will likely change as the character's stats will change.
If you are talking RMU, then I don't know as I haven't sat and read the rules yet. But, from what I have heard is that they have done away with that method of adolescent development, and have instead gone with a set of skill ranks to reflect the character's upbringing. This is sort of like how RMSS/FRP did it, though that still had the player spend DP on an adolescent "level".