new system api invoking the DB

simple eCommerce project,Am new to mulesoft i do have knowledge but hands-on experience is less in mule development and now my task in my team is to develop a raml from scratch, development for that raml and changes in the existing process api for our eCommerce project. the task is simple but am unable to solve it could you let me know this can be done by you then we will connect by today through this Thanks