I would suggest you reach out to your guidance counselor and your local legion post. Some guidance counselors aren't aware or involved sadly. Some legion posts are more active then others.
Our son went this past year and loved it. Our state runs it as it was designed as a mock model of our own State's Government. They were divided into 2 parties, then counties and cities and they ran for office, campaigned, gave speeches, wrote laws and bills etc. He ended up being elected governor and was selected (after applying and interviewing) to represent our state at Boys Nation in DC. His counselor recommended him, the legion interviewed him and he was then sponsored (Legion Post paid his camp costs) by the post for the camp at Boys State. The Legion paid for all of his expenses for Boys Nation as well.
He didn't get much sleep, they hit the ground running early every day and went late into the night. He wrote and gave a lot of speeches.
He made friends he will have for a long time and is in group chats with boys from State and Nation.
What he came away with was how fun it was to spend a week with boys who in his case, were selected based on grades, leadership and character so he was with a group of boys who all had that in common.
He also had an amazing group of counselors who he is still in touch with and who continue to mentor him.
Do your research on your local Legion and State Program. The Legion, Nationwide does amazing things for youth.