How to setup Paypal On Blesta Billing Software

[alexistdev]

I've tried to integrate my blesta using blesta documentation and cant find where is the proper API from paypal. 

Which is there had 3 options API, Braintree SDK integration,Pre-built payment solution,VP/SOAP API integration (Classic).

I dont know where is  the proper IP to connect with my Blesta Software. Since on my blesta required:

API Username:

API Password:

API Signature:

where the those three are located?

regards

alex