How Many Calories Burned?

hey guys how do i know how much calories i burn in a day? i play basketball like 3 hours a day and weight train also for like an hour. how would i know how much i burn

You can use a myriad of equations etc to get an estimate but NONE will be exact and it would vary to each individual and day to day.

Simply try and strike a balance with your intake take some weeks to see what you need to eat to maintain for your activity level and adjust from there for yor goals,