Hi Petula,
As a parent myself, I would say you need to talk this through with your daughter, she probably knows more about TikTok through her friends than most parents! I apply the same process to my kids every time they join a new group or play a new game - go through the privacy and security stuff from the start, together. This will let your daughter know that you are aware of the risks and that you are looking out for them. It doesn't have to be a boring sit-down lecture, just start chatting with her about TikTok and let the conversation flow. You may be surprised how much you will learn, and how much your daughter enjoys educating you!