The first step in starting with bootstrap, is to include the following header/template page. Note that the bootstrap.js entry must be after the jqeury.js entry.
<!DOCTYPE html>
<html>
<head>
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
</head>
<body>
</body>
</html>
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