Hey Hello, First of all understand what is Payment Gateway and how does it functions, read here - https://bit.ly/2W0gfTt
Currently I am using Lyra's Payment Gateway it has easily accessible dashboard and developer centric ability merge to make it the most preferred online platform for transactions.
Lyra Payment Gateway offers several features for rendering the clients with a secure, user friendly and quick online payments. It would be good choice to go for it and carry out hassle free transaction.