I have an idea and I am looking to take it to the next step by developing a MVP. What do you recommend I do? Hire a freelance web developer, find a co-founder, find a mentor?
Find a mentor. A mentor will provide you so much insight that will allow you save time and money on your project. I also recommend you "fail fast". What I mean by that is start taking steps to get data, don't worry about being perfect or making mistakes. You're young and you can use that to your advantage. Look at other young entrepreneurs and learn where they hang out and who they follow on Facebook, Twitter and Linkedin. The mechanics of a business isn't the most important part. It's the implementation of the idea. It's actually "taking action" so you can get your prototype crated. Then you can tweak it and get more data. The exciting part is your in the mindset of working for yourself instead of a boss. That is a powerful mindset at the age of 16 for sure.
I hope this served you.
Remember... be a servant,