Write Simple Javascript Chrome Extension

I would like to have a script written that will essentially automate the following tasks and work it into a chrome extension: Select a value from an html dropdown list, then press a button. On the next page, it will press another button to move forward. Next, it will autofill a set of info (from the code, no need to have an interface in the extension) then press another button. On the following page, press another move forward button, then autofill more info and press the final move forward button. Ideally, this will all be done via pressing a single button. This is a very quick project and doesn't require super advanced javascript knowledge.