Neuroscience is the study of how the brain works. Scientists whose job is to study the brain have found different parts of the brain that control different behaviors or feelings.
Sexual orientation is about who you are attracted to, romantically and sexually. Some people like boys and some people like girls, while others like both, or neither.
Now, scientists have found out that sexual orientation is not a choice, like deciding what kind of ice cream to have for dessert. Instead, it is something that we are born with, like the color of our eyes.
They have studied the brains of people who are attracted to the same gender and found that they have differences in the way their brains work when compared to people who are attracted to the opposite gender. These differences are not something that people can control or change. It just is the way their brains are wired.
So, in summary, neuroscience has helped us understand that sexual orientation is not something that we can choose, but instead is something that is a part of how our brains work.