A reasonably good work, but there are a few areas in which improvement can benefit this:
1 - The text is way too small, making it quite difficult to read, particularly for those playing on older computers with low graphics. Larger text, distributed through multiple pages with a 'next' (and maybe 'previous') button is generally preferred over all of the text squeezed into a single page, like in the 'instructions' option in the menu.
2 - The How To Play option could include the ability to hover over and/or click on specific buttons and see what they do. The setup present in the game as is is fine, but players generally like to have control of everything they do in a game.
3 - The game itself is fairly repetitive; one plays as one character with one small set of abilities, in the same world leveling up perpetually and killing bad guys. Though fun at first, it loses the punch quickly and the player loses interest. Games like this don't usually have a main menu like this one does.
4 - The mute button is on the game area, and is too easily confused with a gold coin or a glitch. Putting it in the black area below the game screen would help.
Apart from that, good work. Give it your best every time, and you'll improve and learn something every time. Best of luck in the future.