Hi @Phu Vuong ,
Welcome to Q&A forum!
According to my research, you may be able to install Office 2019 on an Azure virtual machine. But you may need to install Office by using FSLogix application containers.
For more information: Install Microsoft Office using FSLogix application containers.
Generally, Microsoft Office 2019 Standard/Professional Plus are volume license version.
The ways to activate them are KMS, MAK and Active Directory.
It is recommended that you use Active Directory to activate it. For more information, please refer to: Activate volume licensed versions of Office by using Active Directory.
In addition, since we do not have a similar testing environment, I also suggest you contact Microsoft Support directly to confirm this.
Reference: Office prompts for activation in Azure.
Hope the information could help you.
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