Just Use this code in your custom js file:
jQuery(function() {</p>
jQuery(‘input:text:first’).focus();
var inp = jQuery(‘input:text’);
inp.bind(‘keydown’, function(e) {
//var key = (e.keyCode ? e.keyCode : e.charCode);
var key = e.which;
if (key == 13) {
e.preventDefault();
var nxtIdx = inp.index(this) + 1;
jQuery(“:input:text:eq(” + nxtIdx + “)”).focus();
}
});
});