One of the first modules you’ll want to install into ANY drupal site is Pathauto. This essential module will convert the somewhat ugly url path of “node/123” into the much more SEO friendly versions of “content/relevant-url-name-here”.
If you’ve been mystified by how this module works then this video may provide the guidance you need.
Note: You’ll need to install the Token module as well, in order for Pathauto to function properly!