I want to use a free photo editing and image software...

To get all the tools you need to edit or create original images, spruce up your photos, add some text to a picture or do a little image manipulation, all for free, try using Gimp. Gimp is the very best free replacement for the expensive Adobe Photoshop suite.  Gimp's developers continue to strive to be a high end free software graphics application for any type of editing, including web graphics. Try using Gimp before you invest in any expensive editing software.