If you want to use Spotlight to search for something, don’t bother clicking on the magnifying glass at top right. Just press ⌘-Spacebar and Spotlight pops right up. If it doesn’t, go to Apple menu/System Preferences/Spotlight and make sure the preferences are set that way. See below:
(Thanks, Rick, for pointing out that the preferences might not be set to ⌘-Spacebar.)
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