<form action="/target" class="dropzone mb-2" id="myDropzone1">
    <div class="dz-default dz-message my-2">
        <i class="h1 bi bi-cloud-upload"></i><br>
        <button class="dz-button" type="button">Drag and Drop or Click here to
        upload</button>
    </div>
</form>

<p class="text-secondary small">Upload only .jpeg, .png, .mp4, .mpeg4 file format max. file size 6MB</p>

<script>
    Dropzone.options.myGreatDropzone = { // camelized version of the `id`
        paramName: "file", // The name that will be used to transfer the file
        maxFilesize: 2, // MB
        accept: function(file, done) {
            if (
                file.name == "justinbieber.jpg") {done("Naha, you don't.");
            }else { 
                done(); 
            }
        }
    };
</script>