You'd want to use a combination of WebStorage and Array. Basically, all the in-game stats can be easily kept track of via an array object, then when it comes time to save you can save it all as a string in WebStorage. Here's a really good tutorial on it.http://www.scirra.com/forum/saving-and-loading-an-array-to-webstorage-capx_topic50970.html
That tutorial is as basic as you're going to get with what you're asking for, and it's the best tutorial for it, too.
One thing to keep in mind: it saves everything as a long string, so when it gets loaded back into the game data array all your integers become strings again, so any time you call a variable from the array and expect to use it as a number, remember to use the int(x)
System expressions to stay on the safe side.