A Google Business Profile is the free listing Google shows on Maps and beside its search results. Google says it ranks them on three things: how well the profile matches the search, how far away you are, and how well known you are. Distance is fixed. The other two are not, and that is the work.
I fill the profile out properly, new or existing, and both are included in the monthly plan. The primary category decides more than anything else about whether you turn up, so I settle that first. The description decides almost nothing with Google and almost everything with the person comparing five listings, so I write it for them.
The profile and the website have to agree, and that is why this comes with the build rather than sold on its own. If your name, phone number and hours differ between the two, Google is reading two businesses. Every site I build publishes the same details as the profile and carries them as structured data, so Google reads them rather than guesses. On an older site that mismatch is often something a website redesign has to fix.