JSFiddle - React, Tailwind, and code Playground

HTML

<input id="numeros" type="number" min="1" max="4" value="1" />
<input type="text" class="form-control" id="ncamisa" name="ncamisa[]" placeholder="Tamanho da(s) camisa">

JavaScript

$('#numeros').on('change', function () {
    var nr = parseInt(this.value, 10);
    var inputs = $('[name="ncamisa[]"]');
    var dif = inputs.length - nr;

    if (dif < 0) {
        var input = inputs.eq(0).clone().attr('id', '');
        while (dif++ < 0) $(document.body).append(input)
    } else if (dif > 0) {
        inputs.each(function (i) {
            if (i >= nr) this.remove();
        });
    }
});