If the police are not at the door with a search warrant to enter and search the house then no you do not have to answer the door for police officers.
You can just not answer the door for the police officer and they'll eventually leave or you can just open the door a bit and see what they want but you're not required to talk to the police if they don't have warrants.
The same law applies for CPS "Child Protective Services" workers if they come to your door you do not have to answer the door or let them inside the house.
Never let a CPS "Child Protective" service worker inside your house without a warrant and do not speak to them without a lawyer.
Same with cops never let them inside your house or speak to them about something unless you have a lawyer.