Connecting a third party system using OTCS REST API

Raj2307

We have to connect the OTCS with a web application called Document Locator using the OTCS REST API. Requirements are,
1. Adding a new folder/document.
2. Updating the metadata.
3. Creating a workflow in OTCS and call that from Document Locator.
Can someone help me how to do that? Is there any documentation that I can follow apart from the https://developer.opentext.com/apis page? I am new to the programming so need a bit help on this.