Hi, I am currently in UNI studying Media (Video, Music, Design and also Web Development). As its summer I would love to have a side project. I've been meaning to learn how to create a text based RPG game, I am curious what skills I would need to make a similar game to this game below. I am highly skilled in HTML5 & CSS as well as bootstrap but I am wondering how much harder would it be to aquire the skills for the game below.

Link: Click Here

Screenshots:
http://www86.zippyshare.com/v/4CdaqBJz/file.html
http://www86.zippyshare.com/v/kfA59sBM/file.html