How to would like to create a game like Runescape?

I'm from the UK and am in year 9, I would like to make an attempt at a game like Runescape. I have everything planned out from the world to NPC's to the weather classes, races etc. I have taken computer science at school and am excelling brilliantly. I'm learning python and java, have mastered just basic and am an intermediate at HTML. Please do not leave reply's saying I will fail dismally and if so I would like a little partner that could tag along with me and try to make this thing. Please answer soon and if you would like to contact me my email is james-donovan@live.co.uk. Thanks in advance.

I should also add that I shall hopefully be making "models" in minecraft as a little draft and would need help with that as well

This is a word of advice only. Do NOT include anything like EOC, unless you want to lose 80% of the people that play your game.

You should learn how to code C++, Visual Basic, Java, Flash, HTML 5, and some other assorted misc. Coding languages like LUA. As for coding the game, you'll need to either first create a game engine or use an existing one. I suggest Unity. It's becoming more popular as a game engine and it works across multiple devices.

For example, on the flash game website Kongregate, users are able to play multiple games either written in Flash/HTML 5 or written using the Unity Web Player. A few examples of games that run off the Unity engine is the Attack on Titan fan game and the Surgeon Simulator that's hosted on the Kongregate website.

You could also try to make a game similar to Risk of Rain. Risk of Rain is a game written and coded entirely in the Game Maker game production software from Yoyo Games. Its been developed by a different company and is also being produced by a company called Chucklefish.

Thing is, Game Maker uses it's own coding language, but it's a great way to get started with the basics, and then work your way up to Unity or other game engines like the Crysis engine or Unreal Engine(s) often times seen in mainstream games such as Borderlands or Assassin's Creed.