Hi @Ivy S
Do you want to the Developer tab like following image?
If so, please go to File > Options > Customize Ribbon
, tick the box of 'Developer'.
If this step does not work, please check whether there is any related error message.
If yes, please take a screenshot and share with us for better analysis.
Besides, please go to File > Account > Product Information
, check whether Office is Microsoft 365 Apps and whether it is activated.
If it is not Microsoft 365 Apps, you may go to https://myaccount.microsoft.com/, click Apps & devices, and then click Install Office to install Microsot 365 Apps. (Please note, you need to uninstall previous Office on your machine first, restart your machine, and then re-install Office.)
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