I'm 18, can I become a Catholic monk?

I'm 18 years old, I live here in South Florida, and I really want to become a Catholic monk but most monastery sites I go to from around the country only accept either 21+ or even 26+. Are there any monasteries that I can join at my age? I really want to serve God the rest of my life and I want to do it now. I'm a devout Catholic, i've been confirmed, and I'm an American citizen.