How to create a package of a process for the orchestrator upload without using the studio

the statement is not clear enough and can be interpretated in multiple ways. However:

thats the chain: UiPathProject/XAML - Publish/Compile - Result: *nupkg

Find some further info here and also have a forum search by your own:

take a note from the cite:

Maybe you can use NuGet Package Explorer to modifiy an already existing package with the xamls from your publishing request
https://github.com/NuGetPackageExplorer/NuGetPackageExplorer