OK Hrandyrko, I'll tell you my thoughts about your chances of being pro.
Although you've reached 3.5 within one year and a month, i highly doubt you'll reach pro level at an early age (say 18). If you want to become better fast, train regularly.But i believe that if you keep trying and show enough dedication and talent, you'll eventually make it.
First off, you need to have money to travel and pay board and lodging. If you don't have the money, you'll have limited access to tournaments, I mean, there are a lot of tournaments, but they are all distributed across the country.
Second, I don't think you need tennis lessons, unless they are private, but rather to play lots of hours with someone at your level. I take group lessons and I'm not satisfied because they are too short (1.5 hours of tennis, 1.5 hours of training). Besides, they make me play with a kid whose footwork sucks. I'd rather go to my club or pay for a court (too expensive, at least in my country) and play with a friend (most likely my doubles partner) and try to play as much as possible.
Third, I've been told that to enter a Future tournament, if you are unranked, it is possible to enter one, but you need to play the pre-qualification round, then the qualy round, and finally, you'd be playing at the main draw.
Fourth, DON'T WASTE THE SUMMER; In the club where I practice, there's absolutely no one on the courts at noon. They usually arrive at 6 o'clock. play as much as you can, but beware of the heat. Use sunscreen to protect you, replenish lost electrolytes and stay hydrated. We don't want you to have a heatstroke. You'll have to endure the heat to train. You can also train early in the morning on weekends.
Finally, condition yourself physically AND mentally; try to be relaxed and play calmly. Do not fall in frustration, when you're playing badly, you'll play even worse if you are frustrated than if you weren't.
And about school, I was once told by certain coach that you should NEVER leave school, because if you don't make it, you won't have any backup plan.
I hope my advice can help you with this.