Hi @Garima Das
This question seems similar to this thread:
While as mentioned in the link, since it is a very complicated process (which also have Active Directory involved), please consider contacting Microsoft support by phone or email for better support.
If you need assistance with integrating with third-party apps, I would suggest reaching out to the support team of the corresponding product. As these are third-party products, we may not have the expertise to provide extensive support.
To my understanding, in short you may either consider cross-forest migration (onprem to onprem) or cross-tenant migration (online to online) or PST migration if you do not consider using third-party products.
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