Depending on multiple factors such as your gender, looks, smarts (both book smarts and street smarts as well as your Ingenuity) there are myriad ways for a 16 yr old to make money. Legal : job, or work under the table for neighbors, friends, acquaintances, etc, learning a trade and making better money or playing the long game and going to college in the hopes of landing a high paying job in the future, start networking and buying and selling items or trading items of lesser value to people willing to trade more expensive items of greater value for them, or learning skills and offering to teach others for pay, are just a few legal ones. Illegal ones are much more lucrative albeit dangerous fraud, forgery, transporting selling drugs, your body - I know I wouldn't recommend it but there have been 16yr olds of both sexes who have made a killing and a career of it ( i.e Traci Lords... Google her) or exploiting other and arranging liaisons between them and horny old men with money , or online baiting of pedophiles and blackmailing them in person once you gather enough info to prove who they are and that they have something to lose- also a tricky one full of risk and danger, stealing is an easy one if you can be slick check out bombastershop if you consider doing so from stores and need help circumventing alarms and alarm tags - I am not affiliated with them but they are reputable for tutorials on overcoming most stores alarm systems, there is also stealing from peoples homes and cars or stealing the cars themselves which I don't condone but some become proficient and enjoy various degrees of success, e- whoring in which you pretend to be a female or not if you actually are one and finesse lonely guys for their money, the list goes on and on. google zoklet bad ideas for detailed descriptions of more illegal money makers .
And Remember always...."Nothing Ventured...Nothing Gained " Merlin - Disney's the sword in the stone