What “Search Domain” do I use?!?

Can SOMEBODY/ANYBODY provide me with some input on what to add to the “Search Domain” option on iPhone after changing my DNS??? I can’t find much information anywhere about it. I’m fairly new to all this stuff but I’m very interested in the whole privacy aspect of it all, but after adding stuff to my phone it sometimes acts a little strange. Might just have to stick with NORDVPN. I know the Search Domain isn’t a big deal, it’s just pissing me off i can’t find information about it…

In most cases, search domain isn’t useful in this context.

The search domain is a shortcut, so for example I can type office-printer and the search domain of example.com would let my computer know to try office-printer.example.com

This is actually more useful for things other than a browser, although in some cases it is useful within a browser too.

It is unlikely you have much need for a search domain, especially in the context of a publicly available VPN.