JSFiddle - React, Tailwind, and code Playground

HTML

<form action="" method="post">
			
				<legend>Neem contact op</legend>
				<table>
					<tr>
						<td>
							<label for="Naam">Naam: </label>
						</td>
						<td>
							<input type="text" id="Naam" name="Naam" placeholder="Naam" required="required" />
						</td> 
					</tr>
					<tr>
						<td>
							<label for="Email">Email :</label>
						</td>
						<td>
							<input type="email" id="Email"name="Email" placeholder="Email" required="required" />
						</td>
					</tr>
					<tr>
						<td>
							<label for="Seizoen">Seizoen: </label>
						</td>
						<td>									                              
							<select name="Seizoen" id="Seizoen" required>
							<option value="">Kies hier je seizoen</option>
								<option value="Lente">Lente</option>
								<option value="Zomer">Zomer</option>
								<option value="Herfst">Herfst</option>
								<option value="Winter">Winter</option>
							</select>
						</td>
					</tr>
					<tr>
						<td colspan="2">
							<hr />	
						</td>
					</tr>
					<tr>
						<td>
							<label for="benodigheden1">Benodigheden:</label>
						</td>
						<td>
							<input type="text" id="benodigheden1"name="benodigheden[]" placeholder="Benodigheden" required="required" />
						</td>
					</tr>
					<tr>
						<td>
							<label for="ingrediënten1">Ingrediënten:</label>
						</td>
						<td>
							<input type="text" id="ingrediënten1"name="ingrediënten[]" placeholder="Ingrediënten" required="required" />
						</td>
					</tr>
					<tr>
						<td>
							<label for="stappenplan">Stappenplanm:</label>
						</td>
						<td>
							<textarea name="stappenplan" id="stappenplan" cols="40" rows="5" placeholder="Stappenplan" required="required" /></textarea>
						</td>
					</tr>
					<tr>
						<td colspan="2">
							<hr />
						</td>
					</tr>
					<tr>
						<td>
							<label for="Opmerking">Opmerking:</label>
							</td>
						<td>
							<textarea name="Opmerking" id="Opmerking" cols="40" rows="5"...

JavaScript

$(document).on('keyup change input', 'input, textarea', function() {
    if (!$(this).val().replace(/\s/g, '').length) {
        // no text entered, so don't add line
        return;
    }
    var id = $(this).attr('id');
    // Extract name and linenumber from id
    var res = id.split(/(\d+$)/);
    if (res.length < 2) {
        // No line number, so don't add line
        return;
    }
    var newId = res[0] + (parseInt(res[1]) + 1);
    if ($('#' + newId).length) {
        // Not the last line, so don't add line
        return;
    }
    // Add a line, and make it non-mandatory
    $(this).clone()
        .attr('id', newId).removeAttr('required')
    	.attr('name',res[0]+'[]')
        .val('')
        .insertAfter(this)
        .before($('<br>'));
});