Register domain without publishing

Hello WordPress Community,

Couldnt find anything using the search function.

I want buy a Hoster and use www.remarpro.com.

How do I set up my hoster and domain, without going live with my wordpress website and losing the connection of my domain to my construction websoite I am using at the moment?

I want to switch from construction website using my domain to new website using my domain as soon as I am done and happy with the new design.

My goal is to create a new website using www.remarpro.com and as soon as I am done with that, I am going to publish it with my actual domain.