Hi, There's a great tutorial by Winaero on removing and adding language packs using the Run command, and direct links to them all. I really needed this to solve a confusing problem in not being able to uninstall or add a pack properly in the usual way. (Tutorial link below).

I've been struggling to configure my PC to use English UK again. In doing so I broke Windows and went through a bit of a process to get it running again. When I did so, I found that although I could nominally remove and add English UK, there and there was a Windows Update scan when I did so, and then it appeared to have been added,
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it was not available in the Control Panel
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nor was there the usual message that this would be the display language after logging off, on.

Clicking Option did not offer me the usual download option.
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I tried removing the language pack, logging off, restarting, everything I could think of.
I was faced with this- missing options where it says 'Connect to the internet' (which I was) in the Control Panel:
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Also the Region and Language dialogue vanished just after I launched it.

Finally I found Winaero's tutorial and links to language packs.:
MUI Language CAB File - Install In Windows 10

By both removing the language pack in Settings and removing it using this tutorial, then installing it using this tutorial, and then adding it in Settings, I solved the problem, and finally have 'Flight Mode' rather than 'Airplane' on my Action Centre (note 're' not 'er'). (In the UK we use aeroplanes or 'planes rather than 'airplanes'!).

Hope that's of interest.