Should I report it to my boss?

Long story short my coworkers are always saying insensitive and unprofessional things on our lunch break about rape, suicide, race etc... I always just keep my mouth shut because to be honest they’re all older than me and intimidating. A few days a few of them were having a conversation and I kept hearing one of them say the N word, literally like 10 times in one conversation. I have no idea what they were talking about but she wasn’t exactly saying it quietly and it’s completely inappropriate. Plus there were two young girls on work experience sitting in the room, probably about 13 years old.

I think I should report her to my boss but I’m scared of them knowing it was me and treating me differently. I’m also terrified of my boss because he’s also very intimidating and doesn’t usually take these things seriously anyway. I just don’t want to be hearing things like that in a work environment 🙄