NEED ADVICE ASAP😬

I'm in an interracial relationship with my boyfriend of almost a year, I'm black and he's white. My mother is very supportive of us and says as long as I'm happy she is too. My father and stepmother are not as understanding, they constantly tell me that because he's white they don't like him and they don't agree with the choices he's made, he's 18 and I'm 17 so they still have a say in whether I can see him or not. I need advice on how to get everyone on the same page.