the project references nuget packages that are missing code example
Example: This project references NuGet package(s) that are missing on this computer.
Find the .nuget folder in your project folder. Sometimes when you copy the project you might be miss that folder because of its hidden in your project directory.
If you dont miss the folder and still you get the error, hope you can find solution from this link
https://docs.microsoft.com/en-us/nuget/Consume-Packages/Package-restore-troubleshooting#this-project-references-nuget-packages-that-are-missing-on-this-computer