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Much like Windows, Linux has support for four-digit codes that call special symbols. To access the code input, place your cursor where you want the dash and press Ctrl+ Shift+U. You will see an underlined "u" appear. Enter the code you need and the symbol will appear. To create an en dash, press 2013 and then press Enter. To create an em dash, press 2014 and then press Enter. If your keyboard doesn't have a dedicated Compose key, you can assign a key on your keyboard to become the Compose key, which will allow you to quickly create symbols. You should pick a key that you don't typically use. To map the Compose key, open your Settings in Linux, and then select Keyboard Layout. Click Options and then assign a key on your keyboard to be the Compose key. To create an en dash, press Compose and then --. To create an em dash, press Compose and then ---
Use codes to create dashes. Use the Compose key.