Since you have already come out to them, you can't go back into the closet. The best thing you can do is to try to educate them about LGBT+ issues. Try to explain to them that you are still the same person that you have always been, regardless of your sexual orientation. If they are making your feel unsafe, try to find a support system outside of your family in case you need someone else to turn to.
If your family is making you feel unsafe because of your sexuality, and if you still live with your parents or rely on family for financial support, you will want to make sure you can support yourself if you are over 18, just in case they turn their back on you. It is unfortunate, but many young adults find themselves homeless after coming out to homophobic family members, especially those who were raised in very conservative environments.
If your family won't come around, and if you feel unsafe, it is okay to distance yourself from toxic family members. If you are an adult and are living on your own, you may want to take a step back and let your family process your revelation about your bisexuality. Give them some time to come to terms with it. Once you have given them enough space, try to start a mature dialogue with them regarding your sexual orientation once more. You may want to prepare some talking points and research to show them that bisexuality is not just a phase, and that LGBT+ are just like everyone else.