Question Azure digital twin tutorial

I'm trying to complete a tutorial of azure digital twin

https://docs.microsoft.com/en-us/learn/paths/build-mixed-reality-azure-digital-twins-unity/




I just download for github code on unity (https://github.com/MicrosoftDocs/mslearn-mr-adt-in-unity)
However, there are a lot of errors for namespace 'Microsoft'
How can I do for resolving this issues?

 

Perhaps you didn't complete all the steps in the tutorial?