how do i change the wordpress url to a local fdqn

Question

I've created an intranet site using http, css, js and then used IIS to host it. Then just do the site binding and then add a host record into dns (for example) intranet.local for the company employees to be able to go to it in a web browser.

However, I wanted to move to wordpress to make things easier on myself in the long run. After never installing or using wordpress before, I got it installed and the site created... only problem now... how do i change the url?

I know where to change the url, but it seems i cant just type in intranet.local and it just works....I've tried that in the wordpress settings. Doesn't load up anything after. I'd use a dns host record to redirect the 127 ip address to intranet.local but that doesnt work either.

So how do i do it?

Feel free to dumb it down for me, as I've only ever used IIS, so i'm a bit lost with getting this to work so that everyone can just type intranet.local and not http://127.0.0.1:81/wordpress/