I know all the the numbers and I need to create a new group, but I do not want that all the members are able to know each other's numbers.
Is it possible to create a group in WhatsApp where the telephone number is not shared between the users?
The number of a person is the most basic thing that gets shared in WhatsApp, and it might be the only thing you would know about a person.
There are other messengers who work differently, which your public name or username are the basic information that gets shared rather than your phone number. For example, Telegram.
It's not possible. You can create a recipient list, but you cannot find it again on the phone or on the computer for forwarding anything. But you can find this list on the computer and post on it. Then they all get an individual message from you. It would be really great if they made an option for a group where only the admin can see the members and post or a possibility to see the created recipient list again. That would be great for sharing information in schools and different kinds of groups. I think because of fear of spamming, this feature isn't available.