Runescape private server coding help

Hey guys I am a begging programmer I have done multiple basic programs, I have worked with the robot class and key input but my next project I want to make rs private server bot.
Will be doing a thriving bot wish sells the items iy stole. My question is how do get it so it lnks to the game. I know I do not know the terminology sorry but if you understand what I mean I would appreciate your help! All you have to do is show me in the right direction!