Running Npm for Laravel Application

I am trying to run npm run watch in order to implement the changes I performed in my assets files but it isn't working. I am creating a laravel tool.

I have installed npm without any errors but when I run npm run watch I got the following error. Thanks for the help.

            > npm run development -- --watch


        > @ development C:\Users\\Documents\tool
        > cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js "--watch"

        'cross-env' is not recognized as an internal or external command,
        operable program or batch file.
        npm ERR! code ELIFECYCLE
        npm ERR! errno 1
        npm ERR! @ development: `cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js "--watch"`
        npm ERR! Exit status 1
        npm ERR!
        npm ERR! Failed at the @ development script.
        npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

        npm ERR! A complete log of this run can be found in:
        npm ERR!     C:\Users\AppData\Roaming\npm-cache\_logs\2019-08-13T08_58_29_406Z-debug.log
        npm ERR! code ELIFECYCLE
        npm ERR! errno 1
        npm ERR! @ watch: `npm run development -- --watch`
        npm ERR! Exit status 1
        npm ERR!
        npm ERR! Failed at the @ watch script.
        npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

        npm ERR! A complete log of this run can be found in:
        npm ERR!     C:\Users\AppData\Roaming\npm-cache\_logs\2019-08-13T08_58_29_436Z-debug.log