Web Services/API's for Order/Product update

Kentico has a very strong API that you can create your own Web Services/Interface however you wish. Out of the box however, there is the REST services which may be able to do what you are looking for, otherwise there is also the integration bus which is built for this type of thing. I would start there!

Thank you, Trevor Fayas for your reply. In my case I have already placed order & I wanted to check status of my order from external application. I wanted to update/change status of that order from external system. Is there any ready service available in Kentico which I can use to achieve above?

Since you are looking at changing the Order Status from an external system, I would use the REST service. Have a look at the docs ( https://docs.kentico.com/k9/integrating-3rd-party-systems/kentico-rest-service/manipulating-data-using-rest/managing-objects-using-rest )

You should easily be able to access the COM.Order object and update the Order Status using a PUT.