Point of view (PoV) is critical to your story. The authorial decision you make about PoV will set the tone and voice of your work, and influence the reader's perception of your protagonist. It's a decision that you need to make up front, and once you've made it you need to stick to it. It's essential that you know what the options are, what the benefits and disadvantages of each PoV are, and you understand which option is going to work best with your story.