How to provide argument while debugging any program using VSCode, and it accept argument like --x "value"?

The arguments have to be provided in launch.json file. There is a field called args which parameters to be passed. If you have to pass an argument like --x 'value' or like --y=false or like --z, edit your launch.json and in the arg field add your parameter like this-

        {
            "name": "(gdb) Launch",
            "type": "cppdbg",
            "request": "launch",
            "program": "path of the exe",
            "args": [ "--x", "value" ,"--y=false", "--z"],
            "stopAtEntry": false,
            "cwd":  "current working directory",
            "environment": [],
            "externalConsole": false,
            "MIMode": "gdb",
        }