Adding a Facebook pixel to your site will allow you to collect data that will help you track conversions, optimize ads, build targeted audiences for future audiences, and even remarket to people who have already taken some kind of action on your site.
It's a necessity to effectively use any form of Facebook marketing with your website.
Adding a Facebook pixel to your website can be done in a couple simple steps.
Once you are logged into your website dashboard, from the left hand navigation menu, navigate to Settings -> Facebook Pixel.
Once there, you can simply paste your Facebook pixel ID.