Im a home owner 3 weeks. Roommate no lease big mistake hollering yelling at me no rent told roommate to mo e 3 times. Live in California its not comfortable. What should I do in this situation? Thank you.

So, give them written notice, for eviction. It will take some time.. if they threaten, call the police.

But you will have to follow basic eviction rules.

If they have only been there 3 weeks tell them to get out. If you have to go the eviction route, they may be considered a lodger, which is a special situation in CA: California Tenants - California Department of Consumer Affairs