How do I style my HTML page using CSS?
There are two ways to style an HTML page using CSS:

1.  External Style Sheet: This is a separate file that has all the CSS styles and is linked to the HTML page. To use an external style sheet, create a CSS file with the extension .css and add the following line of code in the head section of your HTML page:

```
<link rel=stylesheet type=text/css href=path-to-your-css-file/style.css>

```

This will apply all the styles defined in the CSS file to your HTML page.

2.  Internal Style Sheet: This is a CSS style sheet that is included in the head section of an HTML page. To use an internal style sheet, add the following code in the head section of your HTML page:

```
<style type=text/css>
 /* Your CSS styles go here */
</style>

```

This will apply all the styles defined in the internal style sheet to your HTML page. Note that internal style sheets only apply to the HTML page they are included in, unlike external style sheets, which can be linked to multiple HTML pages.
Now, how do I add a script to my HTML page?
You can add javascript to your HTML page by using the script tag like so:

```
<script>
/* Your javascript goes here */
</script>
```

The script tag can be added within either the `<head>` tags (which will load the script before all content), or within the `<body>` tags, which will load the script after the content above it has been rendered. 

It is also possible to use the script tag to link to an external javascript file like so:

```
 <script src=myScript.js></script> 
```