Google Knowledge Panel is the SERP display that highlights relevant information about an online entity, whether that be an influential figure, a company, or small business. On the other hand, Google Business Profile is a dashboard where you can manage the information that appears on the knowledge panel. Note that what appears in a search for a given business can vary. If your search is on a greater business entity, you may get a Knowledge Panel if there is one. Google Business Profiles would appear for searches for individual locations. A business can have both, but they are designed for different search needs.