Visual Studio comes with a so-called IIS Express which is mostly used for local debugging and testing.
The "normal" IIS is a component of the operating system.
You have to activate it via "Turn windows features on or off".
There you have to select "Internet Information Services".
For e.g. Windows 7 please follow these instructions:
Installing IIS 7 on Windows Vista and Windows 7 | Microsoft Docs[
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If you want to deploy ASP .Net apps to your IIS
you may also have to consider this:
ASP.NET IIS Registration Tool (Aspnet_regiis.exe)[
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