The missing instructions: You are the ‘x’. Your immediate goal is to beat the level by reaching the right side. Press D to walk right one step. You can press A to step back left, but there is never a reason to do so. The ‘~’ and ‘.’ are obstacles; you will die if you walk onto them normally. To safely step onto the obstacles, press W or S to turn your x temporarily into the same character as the obstacle – W for ‘~’,…
Also, The Crying Game was a dude, Lost was all a dream, Maggie shot Mr Burns, and games just aren't fun.
Don't forget that Samus is a girl!