Target _blank help in Bootstrap

Hi all, i have a website/script i am using that uses Bootstrap. Now i am not much of a coder at all, and need a bit of help, or a push in the right direction at least. The url to my website is gamestimeline.com

Now what i really want to accomplish is to have links in the navbar, primarily the outbound links, to open in a new tab. But upon Googling, apparently its not as simple as adding "target=_blank" to the urls in bootstrap.

Also upon Googling, i found this snippet of code that would make it work in Bootstrap, but of course being i am not a coder, this is where i need a push in the right direction, i am unsure how to impliment this in the template i need it in.

This is the code i found that would make links open in a new tab

jQuery(document).ready(function($) {
$(".Item .Message a:external").attr("target", '_blank');
$(" .Item .Message a").attr("target", '_blank');
$('#Menu li:first > a').attr('target', '_blank'); //it is .navbar in Bootstrap
$('.MessageList a').attr('target', '_blank');
$('#Foot a').attr('target', '_blank'); //this called footer .sticky-footer
$('.Attachment a').attr('target', '_blank');
$('.Meta a').attr('target', '_self');
$('a.ReactButton.Quote.Visible').attr('target', '_self');
//for bootstrap themes
$('.navbar a').attr('target', '_blank');//this will make all menu links open in new window
$('a').attr('target', '_blank');//this will make all links open in a new window
$('h3 a').attr('target', '_blank');//this will make category list title links open in new window.
$('a.Title').attr('target', '_blank');//this will make discussion list title links open in a new window
});

Code (markup):

and this is the template i would need to edit (i think anyway lol)


thank-you in advance for any advice anyone could give me on this conundrum lol