Alan and Michael are on the spot IMO!
I myself if I could start all over again, I would start with a ninja 250 or 300
They are fun and inexpensive, tons of them available and very forgiven when you make a mistake
I would also forget about riding the streets, because of safety, insurance, registration and you will not learn anything that you need to know to ride track.
IMO get a small bike and spend your money with some good gear, trailer, gas jug, stands, lap timer, tire warmers, easy-ups, cooler, tires, bike setup and go do track days!!!
When you feel the time is right, get your license and start racing!!!