For those who cannot access using pathfinding

For those who cant access using pathfinding, or are having problems with “All classes missing directive or assembly reference”.
I just found my solution with:
1] In Unity, go to Window/Package Manager
2] Search for your Visual Studio Code Editor package
3] Downgrade to version 1.1.3
4] Close Unity
5] Delete your .csproj and .sln files in your project (do not simply delete these files, save it on another paste in your computer in the case)
6] Open Unity

i’m sorry for my bad english, i’m a brazilian unity programmer, it took a few hours to solve this problem, and i think it may help someone

I had a similar problem, and the solution is for me : Unable to access Using Pathfinding; - #20 by waltermandelbrot