Symptoms

You created a bootable media according to the guidelines. 

You start booting up a UEFI system and there is no option to select a language of the interface.

You try to switch the keyboard layout by pressing Ctrl-Shift and it is not changing. The default EN-US locale is used. 

Cause

The UEFI x64 loader does not provide the language selection on the screen before the bootable media loads the GUI as compared to non-UEFI version.

Solution

1. When you start the UEFI bootable media, press 'e' on the keyboard once you see the black screen with kernel parameters setup.

2. At this moment, type the below parameter:
lang=<preferred language>
where <preferred language> is the language identifier for your preferred language

Language	Language Identifier
English	en
Czech	cs
Danish	da
German	de
Spanish - Spain (Traditional)	es_ES
French	fr
Korean	ko
Italian	it
Hungarian	hu
Dutch	nl
Japanese	ja
Polish	pl
Portuguese - Portugal	pt
Portuguese - Brazil	pt_BR
Russian	ru
Turkish	tr
Chinese - China	zh
Chinese - Taiwan	zh_TW

3. Press Enter to proceed with booting up the media. 

4. The bootable media will now be showing the default language as the one you specified in kernel parameters.

You can now switch from the default language to EN-US by by pressing Ctrl-Shift.