I'm ignoring the age question since it's irrelevant. "How to get a mentor" is to get a job working at a company alongside more-senior developers. Freelancing

I'm ignoring the age question since it's irrelevant. "How to get a mentor" is to get a job working at a company alongside more-senior developers. Freelancing is better for people who are already senior, in charge... people who are the mentor. If you want a mentor then your best bet would be a structured work environment where you're in a position to benefit from someone else's knowledge on a day-to-day basis (as most of those learning opportunities will end up being random and occasional).