Request a PayPal API signature
1. Open API section in settings
Log in to your PayPal business account and click on Profile and open your Account settings afterwards.
You'll see the page you can see below. Click on My selling tools and then on Update in the API access row.
2. Request API access
Click on Request API credentials to generate your PayPal signature.
3. Confirm request
Select Request and API signature and click on the confirm button.
You'll then see your API signature data.
Add this information to your Landingpage. Afterwards your users will be able to make payments using PayPal.