[Vuejs]-Laravel Mix Vuejs component Syntax error on <template />

You’re using laravel mix v6 which adds .vue() to mix.js(...) :

mix.js('resources/js/app.js', 'public/js').vue({ version: 2 })
   
mix.postCss('resources/css/app.css', 'public/css', [
        //
]);

for Vue 3 check this answer