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Please sign in to My Account with your Microsoft account, click VIEW in Subscriptions to check which licenses you have.
Generally, if you have an Microsoft 365 subscription, please deactivate previous installation of Office, then you could install Office on the new PC.
If you have a non-subscription version of Office, it's suggested to uninstall Office from the previous PC, then install Office on the new PC, you may need to activate it by telephone.
If you can't activate Office, you could contact Microsoft support directly.
Hope the information is helpful to you.
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