Hello @naoki ,
Azure is the name of the popular cloud platform provided by Microsoft.
This cloud platform offers access to many resources like databases, websites, storage, networks, virtual machines, etc. And it is offered on a global scale.
Although Azure integrates very well with Office365/Microsoft365, the cloud environment is an independent solution.
To start with Azure, follow this link for free Azure credits.
If you are a student, check this link to see if can start for free with your university or school email.
I'm not sure which resources you are seeing. Azure resources are 'only' accessible using the Azure portal so any resources related to you are shown there.