Please sidePlease check below the topic explained on this page:
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Go to https://developer.paypal.com/ and sign in
Click on My Apps & Credentials (at the Left Menuleft side menu).
Note that you have two options in the first section (My apps & credentials): Sandbox and Live. It would be nice to create an App for both environments, so you can also test your funnels before processing real orders. Then, click on Create App button (see the image below)
After creating the app, you will see a screen like the one below.
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