Just like in the original game for iOS and Android, your objective here is to get around as many pipes as possible without crashing into one. To do soon, you'll need to flap your wings (with the space bar) and keep up a constant rhythm so that you don't crash or fall.
First Person Flappy Bird is just as difficult as the original game, which means that you'll need to practice a lot if you hope to get past even one or two pipes. It's painfully difficult, but it is possible - just practice, practice, practice.
The first-person perspective is the element that is most different from the original Flappy Bird, and getting used to it is another challenge. It does have great graphics.
First Person Flappy Bird is a difficult arcade game with some platformer aspects - but it's exactly that high level of the difficulty that makes it so addictive.