Lawsuit

I need to know if and how to build a case my job is unfair my boss fires people only if she doesn’t like you she lets people get away with tardies and not doing their jobs right because they are family she offers everybody a manager position sneaky to shut them up she she give me a supervisor position then I hear rumors that she’s going to take my position back and my money because the job I work for wants her a white women to be in charge not a black women I do everything right nothing in my file she also makes people write statements against each other I’ve been here for 7 years and I know when something isn’t right she only fired people who she feel like she can’t use or need