HI, I am Dave, I will help you with this.
You can set your own proffered custom Date and Time formats in Windows 11.
Open the Settings App, then go to Time and Language - Language and Region
Click 'Administrative Language Settings'
On the resulting dialog, select the Formats tab and click Additional Settings
On the next dialog, on the Date and Time tabs, you can manually type in your preferred date and time formats, you do not need to use the pre-defined ones.
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