Be sure to check out the official free Azure page to see products that can be used free for 12 months (up to monthly limits based on region and resource):
https://azure.microsoft.com/en-us/free/
- Linux and Windows Virtual Machines
- Managed Disks, Blob and File Storage
- SQL Database and Azure Cosmos DB
- VPN Gateway and Load Balancer
- Service Bus
- And more
There are also several always free products (up to monthly limits based on region and resource):
- Azure Cosmos DB
- App Service
- Functions
- Event Grid
- AKS and Service Fabric
- DevTest Labs
- And more