Elementary school students' group chat

I have a third-grade child at home.

You have a cellphone, but I didn't install KakaoTalk.

But now that I'm in the third year, all my friends are doing group chats on KakaoTalk, and they asked me to install it on my phone too.

But I was worried, so I didn't install it...

I put it on the pad instead because I was curious.

But yesterday, I saw other friends writing curses and chatting in that group chat...

I told them to leave the group chat, and the child left, but the other kids in the group keep inviting him back...

What should I do with this???

Should I share this in the moms' group chat and block the kids' group chat???