Microsoft Certified Azure Fundamentals (AZ-900) is an entry-level qualification focusing on core cloud concepts and Azure services. It doesn’t have any prerequisites so it’s a natural first step on your journey of mastering Azure cloud.
If you have experience with cloud technologies from other providers, you might be already familiar with the basics of cloud computing but that doesn’t mean you should skip this certification. GCP, AWS and Azure have their own peculiarities and despite having seemingly similar offerings, there are significant differences in how their services are provisioned and configured.
Studying for this exam will give you a good overview of Azure-specific terminology and services, and will be useful regardless of your previous skill level.
I recommend the following free resources to help with your preparation:
Chief Information Security Officer Workshop is a collection of on-demand videos and slide decks from Microsoft aimed to help CISOs defend a hybrid enterprise (that now includes cloud platforms) from increasingly sophisticated attacks.