Congrats! I started pitching at 18, and there were no mentors or advisory...
1 - Learn how to code, this will be very valuable in the
future, or at least how to use no-code tools.
2 - Understand the problem that you are trying to solve,
talking to people that have it.
3 - Incorporate the learnings and refine the solution/idea
4 - Build a prototype with no code if possible and try it with
the people that you spoke.
5 - If they are willing to use it them you need to build an
MVP, and or find a Co-Founder that codes or your learn
how to code (on the long run will be better with a co-
founder).
6 - Finding a mentor would be very helpful