How to add new option in "Create Space" dialog to create space with predefined template and parameters using Connect platform?

I wanted to know about the possibilities of using connect the platform to add a new option in the “Create Space” dialog to create space with a predefined template.

I am able to add extra items using “webItems”. but after clicking that I want to open another window where I can ask for some user inputs and after that space should be created with some predefined pages.

Could anyone please help here? Please let me know if any further information is required?