JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdn.jsdelivr.net/jquery.validation/1.16.0/jquery.validate.js"></script>
<form role="form" enctype="multipart/form-data" method="post" id="curso" action="R/rCurso.php">
    <p class="text-muted">Los campos marcados con (<span style="color:red">*</span>) son obligatorios</p>
    <div class="form-group">
        <label>Curso <span style="color:red">*</span></label>
        <input class="form-control" id="ccrs" name="crs" type="text" />
    </div>
    <button type="submit" id="save" class="btn btn-default">
        Enviar
    </button>
</form>

JavaScript

$(document).ready(inicio);

function inicio() {

    $("#curso").validate({
        onkeyup: function(element, event) {
            if (event.which === 9 && this.elementValue(element) === "") {
                return;
            } else {
                this.element(element);
            }
        },
        rules: {
            crs: { // <- must match the NAME!
                required: true,
                minlength: 10
            }
        },
        messages: {
            crs: { // <- must match the NAME!
                required: "Please enter your firstname",
                minlength: "el minimo es 10"
            }
        }
    });
};