Hi @Devendra Andhalkar .
Based on my research, Microsoft do not provide the document about using external IDP to configure Skype for Business MFA. But it seems there is some way to set up multi-factor authentication (MFA) for Microsoft Office 365 with AuthPoint as an identity provider. For more details, you can refer to:
https://www.virtualsecurity.nl/office-365-integration-with-authpoint
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