To create a Paypal App, go and visit: https://developer.paypal.com/developer/applications
You need to be logged in to your PayPal account to be able to access their developer page. So first, login to your PayPal account and then follow the link above to get to their developer page. This should look similar to the one shown in the image below:
Important: Use the "Return URI" field same as the Paypal Callback URL meentioned on the social login setting page. If these entries do not completely match the URL of your website, the application won't work.
Now click on "Advanced Options" under "Log in with PayPal". We'll need to change a few things in this section. You should:
Important: When you copy and paste all the needed IDs and Keys, make sure, that you don't have any empty spaces, either at the beginning nor at the end of these entries. If you have any empty spaces, then the Application won't work and will show an error message when you try to connect to the App.
After you entered the Client ID and Client Secret, click on the "Save Changes" button within the plugin's settings page.