Github.com/orderedlist - hpw tp create such a greta theme?

Hello dear all

fairly new to the Github-Pages.

one question though: - Carol runs a nicely designed page here

she uses the theme (template) from here

question: is it very difficult to install such a theme on any other Github-Page!? #

Look forward to hear from you

hi there - any ideas ? look forward to hear from you
Regards