How to use a page as a parent page and customize on top of it?

Hi All,

I want to use Case Management Form Page to configure it for different use cases (multiple different type of cases with different UI), I wanted to utilize the UI of Case Management Form Page. This will insure base UI remains same and all the different cases development will be done on different form page. Just like when you create a Freedom UI the skeleton structure is same as its parent is  PageWithTabsAndProgressBarTemplate (CrtUIPlatform), I want to do the same with case management form page as right now parent icon appears locked to me.


Let me know if this is possible or require more clarification, thanks for the help and support!
Rishav