I'm working on some Selenium stuff in AWS. Unfortunately, Server 2012 and 2016 (with GUIs) haven't been all that helpful. I've run into quite a few snags. I'm wondering if it would be possible to install IE11 on either a Nano server or a Core server. Any thoughts would be appreciated.
Furthering JBaldridge's answer: You cannot install more than a cmdline interface on Nano - it comes with no interactive interface at all and relies on remote administration.
On Server 2012 and Server 2012R2 core, you can install IE via enabling the Server GUI. It will attempt to fault in the UI stack in two portions: Management GUIs including MMC and Sever Manager, then the full server GUI. Desktop Experience is an additional unneeded layer above that. You may initially get an error indicating you need to provide additional media sources. You can do this conversion with Install-WindowsFeature in Powershell, or with the Server Manager GUI connected remotely.
In Server 2016 you can no longer switch back and forth between Server Core and Server with a GUI.