Hello @Sharma, Amit (DI SW GS&CS AP IN GSS MOM) ,
Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
It means that apt package manager is not installed or available on the machine. You need to install it first inorder to use it. Adding a reference for your help here
Azure XRDP : https://learn.microsoft.com/en-us/azure/virtual-machines/linux/use-remote-desktop?tabs=azure-cli
Hope this helps!
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