How do I assign the licenses I purchased to my other coworkers?
If those licenses were tied to your ArcGIS Online organization, and you are an admin, you should be able to allocate the licenses to users in your org. Log in to your Organization's AGO and click the "Organization" tab at the top of the page, then the "Licenses" tab underneath the main header. Each available license type has a "Manage" link that allows you to select which users have access to that license. This is not a license pool like when using License Manager, so if you have 5 licenses for Insights, only 5 users can be granted an insights license.
Hi @MarindaGriffin Just to add to the above, here is the documentation for doing this as well: Manage licenses—ArcGIS Online Help | Documentation, but @TonyContreras_Frisco_TX has put it very nicely!