Version with debug enabled:

     <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>

Production version:

    <script src="https://cdn.jsdelivr.net/npm/vue"></script>

If you need something more complex, vue-cli has webpack inbuilt:

    vue init webpack my-project
    cd my-project
    npm install
    npm run dev

Or if you need webpack, but not the complexity, swap the word 'webpack' in the above command to 'webpack-simple'.

... Vue has already done the hard work of getting the build apps configured for you.