Developing Magento 2 with 3 websites/stores/domains: How to see what the sites look like when the domains are not pointed there yet?

Magento 2.4.2-p1
Porto theme

I am working on a new Magento 2.4.2-p1 install. I’ve installed the Porto theme and I’m setting up the design. This will have a total of 3 websites/stores each with it’s own domain but the domains are currently resolving somewhere else (to our old Magento production sites). How can I load the websites I’m working on without the domain resolving there so that I could see what it looks like and whether it’s ready before I redirect the domains there?