Highly disagree, teens around the world tend to have normal sexual encounters before that age. By setting a minimum age you are just telling your kid to hide it from you until that age, which will probably result in less safe sex in less safe spaces.
The right way to approach this is to be attentive and communicate with your child so that you are aware of where they are in their life and can talk to them if needed.
If your child is 14 and intends on having sex, you can either show them that they can come to you for help and guidance, or you can show them that they can't, either way they will probably do what they want.
The awkwardness and discomfort of teens having sex in your house is much better than letting them do it behind your back, possibly in an safe way and in an unsafe place.
Not a parent here, but dear god, please talk to your kids about sex as soon as possible 🙏
There are age appropriate terms to use, but essentially children should know about it for so many reasons.
This can help them identify inappropriate behavior from peers and from adults
It teaches them and prepares them for the real world in a healthy way
It mitigates any future awkwardness that can lead to poor sexual education
Reduces the risks associated with sex as they will already be aware of the critical information by the age that they do start exploring
You would be shocked at how early on children will do sexual actions out of innocent curiosity and self pleasure, this can be okay if they are taught about what is acceptable and what is not.
Gives them a good foundation for a healthy understanding of sex and their own bodies