AZ-900 Azure Fundamentals
This is a beginner level exam, and a great place to start for people just getting started with Azure, or who have not taken a Microsoft exam before.
The exam costs $99 to take, but occasionally Microsoft offers exam discounts, look out for these.
You can learn the details of the AZ-900 exam on the Microsoft docs site.
There are many good resources online, free and paid, to help you prepare.
Check out the AZ-900 section of our Azure Study Resources page