select image from existing folder without programming
There is a community module for this purpose which can be paired with a WYSIWYG. It's called IMCE. Alternately, you can look at the Media module in Drupal 7 which can help accomplish a similar thing.

P.S. Have to agree with the commenter. I think you might have answered this searching for "File management Drupal". :) Hint: https://www.drupal.org/node/265416