Q:

Ctrl+Alt+T not working to open Terminal in WSL

I downloaded Ubuntu 18.04 a few days ago from the Microsoft App Store.
I'm trying to carry out an exercise which requires me opening the Terminal.
I was instructed to use Ctrl+Alt+T, but this doesn't work at all. Every time I use it, it makes a weird error-like sound. 
This is  my first time trying to open the Terminal. 
How do I fix this?

A:

By default that is the shortcut, but it might happen that someone have redefined the same.
For this, go to Settings→Devices→Keyboard and redefine or reset to default by clicking on ✕(if previously redefined) beside it the shortcut.

Update:
The above works with Ubuntu OS. Since the OP is using WSL, there are two ways to launch Ubuntu Terminal:

Command Prompt: Command prompt can be launched from Start or can be run by using Win+R an typing cmd. In command prompt , you need to write ubuntu or ubuntu1604 or ubuntu1804 depending on the version you've downloaded.

Using Ubuntu App: You can define its shortcut using app settings and assign it shortcut Ctrl+Alt+T.

But that makes it a Windows question.
For this read:
How to Create Keyboard Shortcuts in Windows 10

