Cannot open solution file in Visual Studio Code
When you open a folder in VSCode, it will automatically scan the folder for typical project artifacts like project.json or solution files. From the status bar in the lower left side you can switch between solutions and projects.
Use vscode-solution-explorer extension:
This extension adds a Visual Studio Solution File explorer panel in Visual Studio Code. Now you can navigate into your solution following the original Visual Studio structure.
https://github.com/fernandoescolar/vscode-solution-explorer
Thanks @fernandoescolar