Hi Jairaj Naruka,
Thanks for posting your question in Microsoft Q&AApps registered in Microsoft Entra (also called Azure Active Directory) have two parts the app registration and the service principal.
Please refer below document to remove an application:
https://learn.microsoft.com/en-us/entra/identity-platform/howto-remove-app
Deleting an app removes it from your tenant and deactivates associated services. Soft-deleted apps can be restored within 30 days if needed.
If You Lack Permissions, you must reach out to your Microsoft tenant administrator or someone with administrative privileges to carry out these actions. Without the necessary admin rights, you won’t be able to access the app’s credentials or delete it.
Once the old app is deleted and all relevant resources released, you can register a new application and assign developers to manage it.
Refer document: https://learn.microsoft.com/en-us/entra/identity-platform/howto-create-service-principal-portal#option-2-create-a-new-application-secret
To get relevant credentials and access details associated with the application, please have a look into the below document https://learn.microsoft.com/en-us/azure/app-service/deploy-configure-credentials?tabs=portal
I hope this helps resolve your issue. If you have any further issues, please don’t hesitate to reach out. I’ll be happy to assist.