READ FULL INSTRUCTIONS!!! At the start there will be a story, just wait it will end. once you are on the selection page change the stuff by using arrow keys, then click on the item/character/stage to select it. each stage has different levels. the field which has traps, and the desert which has enemies. use arrow/wasd keys to move, and space to swing sword.
Sometimes you will get a rare sword glitch don't worry it won't matter in the long run. collab with @Yumsushi_ , if I left something out tell me in the comments.