Unable to add extension in Application foundation Package

Im trying to create extension for Application Foundation package by creating new Model Called Application FOundatin.Extension. After created a new model with new Package by selecting Application Foundation.

Then its created a project . In this project Im trying to extend Workflow class to select extension this optioin is disables.

Please note down this Workflow class is belong to Application Foundation Package.

Is there anythign im missing here.

I think you misunderstood how to create class extensions. You must create a class; there is no menu option for it.

Please read the explanation in AX documentation: Class extensions.

It seems you miss a lot of basic knowledge on AX 7, therefore you should get used to consulting documentation. It will answer many of your questions.