Use the arrow keys to move around. Don't touch the walls (the black) or the cave will collapse and you'll die. To complete each level, you need to collect the gem, which is the yellow thing. On the final level, you need to get to the exit instead and there is no gem to collect. If you die, you must press the green flag to start again! Also, this is probably obvious, use the green flag to begin as well. There are little bits of speech as well, so don't miss those! On the final screen, the winning screen, I advise not moving the character so that you can take full appreciation of the scene! Hope you like the project!
Thank you to @Communist for making the game 'Nirvana- the game.' It helped me figure out how to use the colour sensing thing, and also how to make the sprite move with the arrow keys.