I have created
Package1_Module1 extension.Now I Want to create another extension
Package1_Module2 so it is dependent on
Package1_Module1 so it is add-on
what I have to write in
package textbox and other stuff in dependencies tab ?
AFAIK that approach it's possible for Magento2 (by composer) not for Magento 1.x generally I see that the extensions with dependencies are packed together.
Module1 it's independent maybe you'll want to keep
Package_Module1 to be installed standalone.