ONELINER
subject.onclick = e=> window.scroll({ top: submit.offsetTop, behavior: 'smooth'});
subject.onclick = e=> window.scroll({top: submit.offsetTop, behavior: 'smooth'});
.box,.foot{display: flex;background:#fdf;padding:500px 0} .foot{padding:250px}
<input type="text" class="textfield" value="click here" id="subject" name="subject">
<div class="box">
Some content
<textarea></textarea>
</div>
<input type="submit" class="submit" id="submit" name="submit" value="Ok, Done.">
<div class="foot">Some footer</div>