Yeah boys have a chance of growing until 18 and even up to 21 sometimes, it's more dependent on the individual so you don't really have a way to know. I'd say getting into sport would be the first course of action (this is coming from someone who also spends the day studying or using the computer!). Sports that you can do by yourself which would be good for increasing height are cycling, swimming and running. Going to the gym could help and is generally pretty cheap. Sleep and eat well (this is important and society romanticising a lack of sleep is super dangerous!)
Actually, do all that anyway, not even to make you grow but because sitting down all day at a computer is terrible for your body. You will thank yourself as an old man, while everyone else has back issues because they've spent their lives in an office hunched over a monitor you'll still be pretty fit and healthy.