For most Android phone users, Play Store is already installed on the phone already. It is a portal for you to download and install new apps with just few taps.
The icon of the Play Store: (Shape may vary depends on the Phone model)
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Only two steps, you can find your own Play Store ID:
Step 1: Open Play Store and click the "burger" menu on top:
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Step 2: You Play Store ID is under your name:
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That is it!