My advice is watch the video and read the docs again and again until you have understood the information in them. Your questions and the things you say you have done show that you have not understood it so far.
The hosts file things you have done are correct. But you have not understood what to do in IIS.
You should create a new root level IIS web site and use that, do not use the default web site, do not make a folder beneath a web site nor an application beneath a web site. It should be a root level IIS web site where the basic settings for the site point to the root folder of the mojoportal files. There should be the mojoPortal Web.config file in the root of the mojoportal files. There should not be any other web.config files in any parent folders above the mojoPortal files.
host names point to ip addresses
When multiple IIS Web sites share the same ip address then the IIS site needs bindings to have the host name so it can resolve requests to the correct site. What makes the Default web site the default is that it does not have nay host name headers in the bindings. That is why I say don't use it, as soon as you add it host name to the bindings it would no longer be the default web site.
neither host names nor ip addresses point to folders beneath an IIS web site, together they point to a Site.