How the hell is anyone going to know what the syntax is? It surprises me that the rest of Visual Studio Code is so good, and something as simple as am option to browse to (or even find itself) what some component is looking for isn’t there? Oh Microsoft, you haven’t changed a bit in 30 years! Well here’s what to put in that settings. Maybe it's possible to debug PHP on Visual Studio, but it's simpler and more logical to use Eclipse PDT or Netbeans IDE for your PHP projects, aside from Visual Studio if you need to use both technologies from two different vendors.
Then you think, ah OK, it must be in that mysterious settings.json file, but all that does is to open a new coding window, with two curly braces.