Hi Malinda

I didn't integrate Pearson resources, but we use other LTI integrations from other vendors.
I've found that Moodle docs covered it pretty well: https://docs.moodle.org/403/en/Publish_as_LTI_tool

Sometimes, once you've created a tool via manage tools, you then need to share that information with your vendor (the Tool Configuration Details you get when clicking the eye icon on the tool).

And then in one of your courses if you add an External tool activity, it should let you add the LTI based resource.