Styling can be done in 3 ways:
Inline styling
External Styling
Internal Styling
Inline styling is done by using the HTML "style" attribute.
<div stlye="color:green;">Hello World</div>
Internal is done with a style tag
<style>
div {
color:green;
}
</style>
And external styling is done with a link tag. Place this in the head of the document.
<link type="text/css" rel="stylesheet" href="YourCSSFile.css">
for the building block, i'm not entirely sure what it's asking for, but here's a basic HTML setup
<!DOCTYPE HTML>
<html>
<head>
<title>Page Title</title>
</head>
<body>
</body>
</html>
And I don't know too much about libraries, as I never use them. Sorry m8.