Hello there! Welcome to the Sans Simulator!
If you can't tell by now, this is a fork of the (popular?) game 'Bad Time Simulator', which you can play right here. Anyway, this game is a little different, so let's explain.
The white obstacles damage you if you touch them.
The blue obstacles damage you ONLY IF YOU'RE MOVING.
The orange obstacles damage you IF YOU'RE NOT MOVING.
Use the Z button to advance text, and use the arrow keys to move and jump.