If someone is in your house and won't leave and they do not have a lease or they are not supposed to be there then yes you can call the police to have the person leave.
However if you are renting a room to someone then that makes you a landlord and if the person has a lease then you have to go through the courts to get an eviction done.
Then the police can remove the person.
But if it's just someone you don't want in your house or on your property then you can call the polices non emergency number and tell them you have someone in your house that you want removed.
The police should then show up and ask the person to leave and if they do not leave peacefully and they are trespassing then the police will or at least can arrest them.