How to give Location and TimeZone of the user on a form

Hello,

I got the requirement like we need to show the current user location and time zone on a form, it shouldn't be a auto filled, it should be like a dropdown value with only their specific location they can select, and they can change it to other if they want, without creating a Master table could it be done? If anything related have done earlier, request your help here.

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Bhargavi Katepalli
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