@stephen Makumbi Welcome to the Microsoft Q&A platform, thanks for posting the question and for using Azure Services.
Yes, you are correct that you have a subscription quota for which you pay nothing unless you exceed it. However, you will still be charged for any active resources that you have created, such as App Service, App Service Plan, SQL Database, and SQL Server, even if you have not exceeded your subscription quota.
This is because these resources consume compute and storage resources, which incur costs. Therefore, it is important to delete any resources that you are not using to avoid incurring unnecessary costs.
You can also set up alerts to notify you when your usage or costs exceed a certain threshold.
I hope this information helps, let me know if you have any additional questions.
Regards
Geetha