这是一个windows环境，但我认为这将是类似的。
我为每个项目都准备了一个launch.json文件，如下所示，我可以在其中选择我安装的PHP的许多版本之一。

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [        
        {
            "name": "Debug currently open script",
            "type": "php",
            "request": "launch",
            "program": "${file}",
            "cwd": "${fileDirname}",
            "port": 9003,
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php5.6.40\\php.exe",
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php7.0.33\\php.exe",
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php7.1.33\\php.exe",
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php7.2.34\\php.exe",
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php7.3.32\\php.exe",
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php7.4.32\\php.exe",
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php8.0.25\\php.exe", 
            //"runtimeExecutable":"C:\\wamp64\\bin\\php\\php8.1.14\\php.exe" 
            "runtimeExecutable":"C:\\wamp64\\bin\\php\\php8.2.4\\php.exe" 
        }
    ]
}

如果你做一些类似的事情，你可以让VSCode启动任何版本的PHP你有你的系统