csrf mismatch laravel 8 Fixed

You need to do it something like this, Add header in your ajax

    $.ajax({
        headers: {
           'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
        },
        url: 'upload.php',
        data: form_data,                         
        type: 'post',
        success: function(response){
            alert(response); 
        }
     });

And now you should have below given meta tag in head of your HTML

<meta name="csrf-token" content="{ csrf_token() }">

This will fix the csrf error.

or

try this

        $.ajax({
            url: 'upload.php',
            data: {
                 "_token": "{ csrf_token() }",
                 "id": id
            },                         
            type: 'post',
            success: function(response){
                 alert(response); 
             }
        });