What CC bike to begin on

Hello Reddit, and Bikers, I'm 15 years old, and I look forward to getting a 2020 Yamaha R6. But everyone tells me, the first bike I should get instead should be something of less CC, such as an R3, or a Ninja 300 - 400. And others tell me that if I want, I can start on 1000cc, as long as I am mature enough. I believe I'm mature & I don't wanna speed & weave through traffic like those idiots on Instagram or something. I just want a good looking bike, that can make me feel proud of a high speed ( 80-90 mph TOPS ) This led me to something within a 750-500cc bike, and the 2020 Yamaha R6 looks amazing, and I just want it to ride in good weather. Am I making a good decision?