Use the arrow keys to move. Click the button in the top right corner to enter build mode. While in build mode you can't move but you can drag the floating ground into place. Use the floating ground to build a path to get to the other side. Keep in mind that some levels have "hidden" things that you can move or that help you out. Every level is possible.
Also please check out the Building Boy Studio for more versions of Building Boy. I'm not sure how I feel about this one so comment how it is.
