How to Make a Game Like RuneScape

Figure out what you want in your game, make a list with things you really want in your game and put it in a locker until you reach a specific step beneath.

Download 3Ds max or buy it (pretty expensive, but do you want new handful updates? Buy it and you support autodesk) and follow the tutorials. 3Ds max is a very difficult program, but it is used for animations like "Finding Nemo". What you do in 3DS max is you create the models/characters used in the game and so now create a simple character, save it, create an environment, save that, make a turret (enemy that shoots frequently at you, could be an archer/cannon/guy with guns) and save that (all those files should be saved separately).

Download/buy unity 3D, (this is your engine,) and again follow many tutorials. Create a new scene where you separately load the 3 files and put them together, with a few scripting learned by the tutorials the turret shoots at the character you can steer and attack back.

Make a whole world and enemies. This is also the time to pick up your list and scratch things and add them to your game.

Use music software (like fruity loops) to make specific soundtrack. Music could be very important. Do not forget to make trigger sounds like gun sound, walking or shouting.

Search for a server and create your own website. Do this by making it attractive so you can pay your server payments back with "google ads".