How To unlock and save levels in Corona SDK

Hey guys I am new to Corona SDK I have worked in other languages like java and game salad. This is my first time working with lua,and I love lua so for. But now to my problem I want to unlock levels in corona and have a 3 star system like angry birds but I don’t have no idea how to do this. Also I have 34 levels and I want to know if I have to create 34 lua files one lua file for every level. How would I solve this this issue thanks in advance. Some please help:)…