Menu Path: Income > Business Income > Business Income (Schedule C)
Depending on the type of income it's reporting, a 1099-MISC may need to be assigned to a Schedule C, Schedule E, Schedule F, Form 4835, or just be reported directly on Form 1040.
You can assign your 1099-MISC to a business (Schedule C) on the Attach 1099-MISC screen of your Schedule C.
On that screen you'll see a list of unattached 1099-MISCs. Check the box to attach the 1099-MISC to the business.
If you need to enter a 1099-MISC for your business, answer Yes to the question on the Attach 1099-MISC screen that asks if you received a 1099-MISC for your business.