I don't think you will be able to write a game or an app in HTML, which is really just used for displaying webpages.
If you don't know anything at all about programming, you might want to start with Khan Academy's Intro to JS: Drawing and Animation, which is free. (
https://www.khanacademy.org/computing/computer-programming).
Once you get a little experience under your belt, you could try "The Complete iOS 9 Developer Course - Build 18 Apps" course on Udemy (
https://www.udemy.com/the-complete-ios-9-developer-course/). The course description says it is suitable for a beginner, but I think it would be a bit of challenge for someone without any programing knowledge at all. If you search around the web you can usually find a coupon that brings the cost down to $10-20.