To view webpages with JavaScript, you need to ensure your browser has JavaScript enabled. Generally speaking, you can still view the webpage without JavaScript, but you will not be able to take advantage of the JavaScript functionality.
You normally do this by checking your browser's options. This will depend on the browser you're using. Instructions for some of the more common browsers are below:
You simply go through the steps above but ensure the JavaScript options are not checked/selected.
If you're developing web pages with JavaScript, it's good practice to view your website with JavaScript disabled. This will show you what your website will look like to users who choose to disable JavaScript.
Most (if not all browsers) give you the option to enable/disable JavaScript. If your browser is not listed above, the steps above will give you some idea of how to find it. Just look for something called tools, options, preferences or something similar.