How to enable users editing their CiviCRM profiles details from their Drupal user page?
Create a CiviCRM Profile (or reuse one of the existing ones) by going to Administer >> Customize Data and Screens >> Profiles and set it to be enabled on "View/Edit Drupal User Account". Then the user will be able to edit their details from their Drupal user page.

See this Demo Profile on CiviCRM Demo site and notice that "View/Edit Drupal User Account" is checked. Take a look at this tab on the Drupal user page. The fields in the Profile can be edited.

For more details see: the CiviCRM book section on Profiles.