Like in candy crush or other games when you have completed a level the menu screen is a map which shows you how far you've got how would you be able to do this? If you can help it would be a massive help as im new to all this
In terms of what? You would have to make some graphics. You can unlock levels based on global variables.
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In terms of keeping the information in between plays, you want to look into the local storage object and storing information with that.