Many cities and states have bike lanes and laws that protect bicycle riders. But riders are still at risk of being hit by cars. Therefore, you need to ride carefully, obey the laws, and watch for other vehicles. Always be prepared to stop or take evasive action.
The brain is fragile and easily injured. Even a simple fall can cause brain damage that may leave you with lifelong problems. When riding a bike, everyone, including adults, should wear helmets.