I'm setting up a Facebook pixel. I know there is the integration, but when I've tried using that it selects the wrong tracking pixel by default and won't let me change it because it says I'm not an admin even though I have "Full Permissions".

So I'm setting up the Facebook pixel manually as a custom pixel. I believe I got the initialization code installed (minus the HTML tagging since that apparently doesn't work with Shopify's pixel thing). However it says I need to "subscribe to events". It just redirects me to API documentation about pixels.

Could someone explain in simple terms what I would do to turn on specific tracking for these events? I have the Facebook event tracking code to call on each event, I just don't know where I would place this code.