A variable is a named value in the current shell. Exported variables also reach child programs. Expand a value with a dollar sign and quote the expansion when spaces may be present. Single quotes preserve the dollar sign instead.
A hard-coded printout doesn't configure later commands. Export the setting, then verify the value the shell expands. Read the requested key carefully; similar names are separate settings.
Write REGION=east without spaces around the equals sign. Then export REGION if a child script needs it. An ordinary assignment remains local to the current shell. Printing the value with printf verifies the text, while env lets you inspect exported settings. A correctly spelled key with an empty value is still different from a misspelled key.