Can IIS Express and IIS be installed on the same machine?

Yes, you can.

Where do I find the IIS EXPRESS installation files?

You can find it here:

https://www.microsoft.com/en-us/download/details.aspx?id=48264

You can install it on these systems: Supported Operating Systems

Windows 10, Windows 7 Service Pack 1, Windows 8, Windows 8.1, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2

You can run it immediately after downloading and running from your chosen location.

These are the benefits of using IIS EXpress:

• The same web server that runs on your production server is now available on your development computer.
• Most tasks can be done without the need for administrative privileges.
• IIS Express runs on Windows 7 Service Pack 1 and all later versions of Windows.
• Many users can work independently on the same computer.

All information from Microsoft Site.

How do I run IIS Express from command line?

Make sure you have installed it on your machine by checking C:\IISExpress /?

Then you can access using the command line.

Please refer to this document:

https://docs.microsoft.com/en-us/iis/extensions/using-iis-express/running-iis-express-from-the-command-line

What are the differences between IIS and IIS Express?

 There are a number of differences. 

Here is a table I extracted from the Microsoft website:

Can I manage IIS Express in IIS Manager?

 The simple answer is no. 

IIS is managed by IIS Manager and appcmd.exe

IIS Express is managed by Appcmd.exe

IIS Express Management tasks are built into:

WebMatrix

Visual Studio 2010 SP1 and later versions