How can I send information when a order is completed to my own POS?

I have a POS made in PHP using OOP. Also I have my e-commerce in WordPress. So I would like to send the data when a order is completed to my POS.

I already looked up for add_action and the hook of Woocommerce order completed. So now I’m stuck about how to send the information to the POS.

Some ideas to research a bit more? I saw the API of Woocommerce, but my question is how can I make it automatically? The API could work for this?