lost project, when opened scripts are there but nothing in hierarchy like a new project

Lost one project after updating unity so started up a new project and kept to one version of unity fearing what happened to my first project.
After sinking tens of hours into this one I opened my project and without any warning the same thing happened, scripts and assets are there but nothing in the hierarchy and scene window, like I just opened a new project.
I did get an error this time that reads “Could not load symbol clCreateCommandQueueWithProperties : The specified procedure could not be found”
I don’t want to waste the money I have paid for this course but I cant lose a half finished project again can anyone suggest anything that might get my projects back to how they were.
Thanks for reading, sorry if i went on but very stressed.

It sounds to me like your scene just didn’t get loaded. When you open the unity editor, it will try to open the last scene you had open. If it can’t do that for some reason, it will default to opening up a new, (mostly) empty scene. You must have a scene file (a file with the .unity extension) somewhere inside your assets folder, as that is the only way to have a saved heirarchy that persists across restarts of the editor. The default scene that all projects start with can be found at Assets/Scenes/SampleScene.unity, start by checking there. If there are no files with a .unity extension anywhere in your Assets folder, your only option is to restore from a backup.