You supply the form, we supply the backend.
<form method="post" action="https://formowl.dev/@/{form_id}">
<label for="firstName">First name</label>
<input name="first_name" id="firstName" type="text">
<label for="email">Email</label>
<input name="email" id="email" type="email">
<input name="_honey_pot" type="text" style="display:none;">
<button type="submit">Submit form</button>
</form>