Husband and stepmom have Covid

2 of the 3 people I live with have Covid. I slept next to my husband and he’s now super sick and tested positive yesterday, I tested negative though. My dad is also negative despite sleeping next to my stepmom. We’re both isolating in the living room but is there anything I can take to make sure I don’t get Covid (idk if anything even exists)

I’ve never got Covid before but my SIL got it at 30 weeks pregnant and her placenta died at 32 weeks so that’s a big fear of mine.