To open the Developer Account Settings click the Developer from the main page of the PayPal account as shown on the screenshot below.
Then you should Log in to Dashboard.
Afterward, go to the My Apps & Credentials section. Here you should select your account type - choose between Sandbox and Live.
Click the Create App button and enter the required information.
After creating the app, the webpage with the Client ID and Secret Key will be available.
To see the Secret Key, click on the Show button, as shown above. Copy Client ID and Secret Key.
Now, you should open PayPal Settings. To do this, go to LMS Settings -> Payout -> Payment method for payout. Click on the PayPal settings icon.
Here you should fill out the form, using the Client ID and Client Secret from above.
Return to App settings and scroll down to the Webhooks section. Click the Add Webhook button.
In the opened tab you will need to fill a field Webhook URL.
In order to get the Webhook URL, open Payout settings and click on the PayPal settings icon.
Below you will find the Webhook URL. Copy it.
Paste the webhook URL into the required field in Sandbox webhooks.
Then, to display all transactions in the PayPal account you should check the All events box as shown below.
Save all the changes. After this, the Webhook ID will be generated.
Copy the Webhook ID and go to LMS Payout settings.
Paste the Webhook ID to the required field, check the Verifying webhooks box, select the PayPal mode, currency, and save settings.