InDesign is not an image editor. You can't open images; you can only Place them.
When you have an image in InDesign you can see it in the "Links" palette. The you can right click on the entry and choose to edit it e.g. with Photoshop. The image will open in PS. Make your changes and save your work. Close the image. InDesign recognize, that you have made changes and will refresh the linked file.
As John said: You cannot edit pixel graphics directly in InDesign.
btw: Vector editing up to a certain point is possible. For detailed path transitions you will need to open Illustrator. But for most of the basic actions ID is just fine.