JSFiddle - React, Tailwind, and code Playground

HTML

<div id="textfield">

</div>
<input id="inputfield" type='text'></input>

CSS

body {
    background-color:#424242
}

#textfield {
    background-color: white;
    width: 200px;
    height: 300px;
}

.doggy {
    display:inline-block;
    padding: 5px;
background-color: indianred;
    color: whitesmoke;
}
}

JavaScript

$("#inputfield").on('keyup', function(e) {
    if (e.keyCode == 13) { 
        $("#textfield").html('');
            for (var i = 0, len = this.value.split('doggy').length; i < len; ++i) {
                var sp = document.createElement('span');
                $("#textfield").append(sp);
                $(sp).text(this.value.split('doggy')[i]);
                if (i!==len-1) {$("#textfield").append("<span class='doggy'>DOGGY</span>"); }             
           }                    
    }    
})