Try to get started with these answers and then tell us where you get stuck. You have a lot of different questions here so, giving us details about where you have a problem will help us help you.
Can you please give me example how to use Python classes and calling them in test complete.
There are lots of good Python references here:
https://support.smartbear.com/testcomplete/docs/reference/language/python/index.html
I would like to create object file for each page - where all the objects of that page is identified and will be used in projects.
That would be NameMapping
please help me how to organize find child method
With FindChild, you don't usually have to have a full list of every object like you've asked for above. You can have a high level mapping and then use FindChild for lower level objects.
