Being 6'4" in height, you may find the Honda Rebel to be on the smaller side, particularly in terms of its physical dimensions and riding position. The Rebel is a lightweight cruiser-style motorcycle with a low seat height, which may not provide the most comfortable riding experience for taller riders. It's always recommended to sit on the bike and take a test ride to assess the fit and comfort before making a purchase.
As a beginner rider, it's important to choose a motorcycle that is suitable for your skill level and experience. While the Honda Rebel is considered a good entry-level bike for learning, you may also want to consider other options that offer more room for your height and provide a better fit. There are larger cruiser-style motorcycles available from various manufacturers, including Harley-Davidson, that may suit your preferences and offer a more comfortable riding position.
Regarding the concerns raised by others, riding a motorcycle comes with inherent risks, as with any form of transportation. However, with proper training, safety gear, responsible riding, and adherence to traffic laws, you can greatly minimize the risks and enhance your safety on the road. Taking a motorcycle safety course, wearing appropriate protective gear (helmet, gloves, jacket, pants, and boots), and practicing defensive riding techniques are crucial steps to ensure your safety.
Remember that riding a motorcycle requires skill, awareness, and caution. As a new rider, it's important to start with proper training, gradually build your skills and confidence, and always prioritize safety.