It is easy to talk about sex with children, but it is very embarrassing in practice ... because when we were growing up, the topic of sex was taboo, which naturally affected the way we talked about sex, even though we now understand that sex is justified. My personal suggestion is that if you haven't figured out how to answer, don't force it.
It is the best way to give children a sex education book that they have read and recognized and is suitable for their problems. Secondly, tell the child, "Mom hasn't figured out how to answer you yet. Can you wait for a while?" Take a little time to sort out your opinions, want to understand why you are embarrassed, think about avoiding embarrassment, and then answer your children better.
At the same time, no matter how open our own sexual concepts are or think we are advanced. The society we live in is not a society where we can openly discuss sexual topics. Therefore, it is necessary to educate children: don't talk about sex in public, and don't take the initiative to talk about sex with friends. This is not something advanced and backward, but a civilization that respects others and our social culture.
Children's sex education preparation, please be prepared from the birth of the child. Because you really don't know what kind of children you have. The only answer I can think of is: early education for parents. Watching TV with children, hugging and kissing the camera, just like watching ordinary TV. And if you see a picture about sex, you will calmly change the channel while nagging: Hey, how can such a private thing be seen by others?