Theo, it is possible dependant on you web host. If they have cpanel (which most hosts seem to have these days) you can set up a username & password protected webpage/s.

Below is a link to such an example webpage.

On opening it requests username and password. Visitors nor search robots should be able to view the content without this.

Try opening it first then add the following details:

Username = choral
Password = Theo2022

WEBPAGE LINK