Exam DP-300: Administering Relational Databases on Microsoft Azure

Hi sir MVPromise 

You can learn here different database instance available based on your preference :

Microsoft Fully managed intelligent database services


ALso, read the different Application Architecture Guide  

Here is different certification that you can achieve with great documentations , i have include 2 link that will guide you to relational database learning path. You can customize your Learning Path also with your own preferences.

Microsoft Relational Database Certification 

Data Related learning path

Enjoy!