How can I add/remove/update (items and item stock) in a square pos from my next.js project?

Question

I have a next.js website complete with creation, deletion, and updating of clothing items. I'm using aws dynamodb to store all of those and it works great, but my client told me now that they also want to use square as their pos for the physical store. I know square has APIs for payment processing and I think I saw something about catelogs for adding items, and inventory for managing the stock of those items, but I am not sure that is what they are used for.

I would like to have a way so that when someone buys something online, I can send a call over to the square side of things and it will adjust the stock as needed. Or when someone creates an item on the website it would create it on the square side as well.

Question: Is there a way I can keep the square side and the aws side of things up to date with each other?

If anyone can give me some resources that go over how to do this or a piece of code that would help me get on the right track, that would be FANTASTIC!

Let me know if I was clear enough in the question, Thanks:)