Is schedule C and a business required if a 1099NEC is received?

I received 1099NEC because I taught a lecture in another university. I added the amount from 1099NEC as an income and entered "teaching" as the reason for this 1099NEC form. Next Turbotax is asking me to select the business that generated this 1099NEC, and "teaching" was listed as the default option. When I selected "teaching", somewhere in Turbotax also implied that I will later file schedule C. I am very confused. May I ask

 

1. It seems that because I have received an 1099NEC form, Turbotax thinks I have registered a business. However, I have not registered a business. How shall I make it clear in Turbotax?

2. It seems whatever I entered as the reason for the 1099NEC will be defaulted as the name of a business, and I have to specify a name of the business. How shall I honestly enter the reason "teaching" for the 1099NEC form, but do not make it the name of a business (since I never registered a business?)

3. Is schedule C really required for me?  How shall I make it clear that I have not registered a business, and schedule should not be applicable to me?

 

Thank you!