It’s likely that IIS hasn’t been pre-installed with your version of Windows Server 2019.
Details for adding IIS to Windows Server 2019 are given below:
Start by opening the Control Panel and clicking on Programs.
An option is shown for Turn Windows features on and off. Click on this.
A page shows with a summary of the wizard’s actions regards roles, services and features. Read through the content and if you don’t wish to see this again there’s a checkbox to enable skipping of this page by default. Maybe leave it un-checked for now. Once you have taken actions which show the dialogue a few times then opt out. Click on the Next button at the bottom.
The next screen presents the option to select between two radio buttons. Select the first: Role-based or feature based installation. Click the Next button.
On the next page select the destination server. This will be the server being configured. Review the details Select a server from the server pool and from the server pool our named server. Most likely the only server listed. Click Next.
Scroll down the list of available Roles selecting and ticking the box along side Web Server (IIS). This will open a popup window. Add features that are required for Web Server (IIS). The only entry given was Tools IIS Management console. Click on this to highlight it. Click the button Add Features.
Back in the Select server roles screen click the Next button.
Review the asp.net framework options. Click the Next button.
The next page gives a review of the Web Sever Role (IIS). Click the Next button.
Review and select the related IIS role services for example you may wish to include: HTTP Redirection.
Click on the Next button.
Review the list of actions and tick the checkbox for:
Restart the destination server automatically if required.
Click on the Install button.
