My friend doesn't use protection 😕😕

Ugh I need some advice. My good friend and her boyfriend never use a condom, birth control or plan B. They've been together for 2 years so they've been having sex for a while. We had a sex Ed presentation yesterday since the seniors at my school needed to have one and they talked a lot about protection. I think a lot of people got into it and had their minds changed, even one of my friends. But when I asked my good friend if she's gonna start using protection now, she said "Eh". I just don't want her to catch anything or get pregnant. Ik its not my business, but 2 girls we knew are pregnant rn and 1 girl just had a baby. I don't want that to happen to her. What should I do? Leave her alone or keep persisting?😕