Microsoft 365 devloper account will be avilable for 90 days and will be extended if you are using it.
To create a developer account follow the below steps
Navigate to https://developer.microsoft.com/en-us/microsoft-365/dev-program
Benefits
Select anyone
Select your choices
Select region and enter the admin user name and password which you like to create
Provide phone number in next screen . After that your account will be created.