How to create archive split into two pages?

Hi,
I’ve installed this theme: http://graphpaperpress.com/themes/f8-lite/
But what I want is to have the home page which displays recent posts, then a page called ‘posts’ within which there are two sub-pages of ‘architecture’ and ‘photography’.

I can’t find any page templates such as ‘archive’ in the wordpress page menu. I also don’t know if it’s possible to split the archive into two categories in this way?

Here’s the link to my website: http://www.joshuahovey.co.uk