Need Help inputting a third part API Keys onto SquareSpace

Hello, I'm trying to Integrate S&S Active Wear API Keys to my Squarespace website, but I don't know how to add those API keys to Squarespace. I have API keys on another website called S&S Active Wear. I want to integrate both Squarespace and S&S Active wear with the keys I got from S&S Active Wear but I don't know how. I have the API keys for S&S Active wear, but don't know how to input them onto Squarespace