I am new to bitcoin technology, I want to build Altcoin payment button with 2 bitcoin addresses, first is my site address where I will receive a small commission fee, second is my site seller address. When a customer pay, bitcoins will be send to both addresses, is that possible? Thanks
As others have said, you need to build your own smart contract to be able to fulfill your request.
So the question is, are you technically enough to create your own smart contract? If not then I will suggest that you don't make things complicated for you in the beginning. It might take you a bit of your time to send it manually and break it down to 2 addresses, but it is safe for you in the beginning.