Choosing the right motorbike or scooter for you is not really something anyone else can do for you, but I will offer some advice, based on my knowledge and experience as a scooter rider. I see many of the other answerers are suggesting you go bigger. But there are many reasons why you might not want to do that.
For one thing, in many states, anything with a 50cc size engine or less does not have to be licensed. So that might be what you’re looking for. Getting a license to ride bigger machines involves first a regular drivers’ license and then getting a motorcycle endorsement on top of that, which for young people of your age usually means attending a certified training course first. That can all take more time and money than you might want to spend at this point in time.
In addition, 50cc motorbikes are probably going to be quite a bit cheaper than larger bikes or scooters. And I’m guessing at your age, you might not have unlimited financial resources. So I’m going to assume that you already know that a 50cc size motorbike is what you really want.
However, you’re fairly tall and probably haven’t stopped growing, so a 50cc might seem small to you. The best way to know what kind of bike you want is just to try some on for size, so to speak. Go to a dealer and sit on some different models of 50cc motorbikes to see what feels right. Check for features that are important to you, such as storage, ease of use, etc.