@Pradeepa Baskar Thank you for reaching out to us, Azure AD & Azure B2C are different, hence both have different P1/P2 licenses.
Following table explains the difference between Azure AD & Azure AD B2C, also it explains about P1/P2 what it offers.
Reference:
https://learn.microsoft.com/en-us/azure/active-directory-b2c/supported-azure-ad-features
https://learn.microsoft.com/en-us/azure/active-directory-b2c/billing
https://azure.microsoft.com/en-us/pricing/calculator/
Let me know if you have any further questions, feel free to post back.
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