Adding navigation is very important when making a game. You have to know all the buttons you can use to make the game properly. To find how to use the navigation keys you can go to http://www.thesitewizard.com/wizards/css-menu-buttons.shtml.
Keyframes are very important when trying to make a game. You use them by clicking the open circle and dragging it to what ever number you want. That will then make your game start moving if all your codes are right. keyframes are probably one of the most important things needed to create a game.