From what you described it sounds like you don’t have cross-domain linking setup. If you have the HubSpot tracking code on your website and cross-domain linking active it will show the contacts original source.
So depending on how the contact arrived on your website, HubSpot will assign the original sources as per this knowledge base article.
Upon conversion, you will be able to CTA clicks in the contact’s activity feed, and analyse CTA performance in the CTA tool.
I hope that helps.
Frank