How to modify admin pages? Everytime I log in into the Drupal site there is a resume of the posts that I have written. I would like to modify it and show all the accumulated views of each user post.

I plan to use the Views UI to make the query but I am not sure which file modify to change the admin site.

Thanks.
If you are meaning the Drupal dashboard (admin/dashboard), there is a documentation page on how to customize the dashboard.

If you want to go further on the customization of the dashboard, there are modules like Homebox that can be useful.