Hi @IniobongNkanga-8038 ,
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Based on your description if you mean "Migration tenant to tenants", please kindly check the article Microsoft 365 tenant-to-tenant migrations - Microsoft 365 Enterprise | Microsoft Learn for more information as Azizkhon Ishankhonov said.
If you want the cross-tenant mailbox migration, you could follow the steps below.
1.Preparation: Before you start the migration, you need to verify that the prerequisites for the migration are met. It is important to avoid conflicts by comparing UPNs, email addresses, and other identifiers.
2.User and group migration: If you're migrating users and groups, you'll need to create new users in the new tenant and add them to the appropriate groups.
3.Licenses: Make sure you have the licenses you need for cross-tenant migration.
More information can be found Cross-tenant mailbox migration - Microsoft 365 Enterprise | Microsoft Learn.
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