Change from Localhost/eample to www.example.com for intranet

Hi

I had this question raised before also but seems to be my question is not clear enough.

And also iam new to this.

I have made a site in wordpress in 2008r2 with IIS for an intranet website for our company.

Nb:In IIS under default website i have added this as an application.

Now everything works fine.
to get my website i type localhost/example in browser and it shows.

Now what i want is instead of typing localhost/example i would like to enter https://www.companyname.com to get the site opened and this is for only intranet.

What are the steps that i have to do to acheive it.

Pls explain in detail because i am new to this.

Thanks
Fiyas