List Specific Categories in a Page

Hey all,

i need help on how to create a page which will list category names with their thumbnail.
i have a lot of categories since it’s a video website, what i have for example:

Movies:
-Action
-Comedy
.. etc

Tv shows:
-Got
-Sherlock
..etc

when i use “Category Template” while creating a page it will show me all of the categories i have, and what i need is creating a page the will list the sub-categories of “Tv shows” only.

i hope my question is clear and you guys can help me out.

Thank you