Hello there. I am not familiar with this theme but if you log in and turn on the editing on the front page, do you then see the option to "add site news" as I think the image and text on the front page are probably coming from the site news (I might be wrong) Could you post a screenshot of how it looks once you have logged in and have the editing turned on?
The theme was developed by my developer who abandoned me...smh! I do not see the option "add site news" when I go to the theme itself which is called 'lamppost' I see a 'box' around it and it says "use for modern browsers" "Use for old browsers"
These were options that could be clicked but I can not click them now.
My site looks like the moodle-lamppost.png that I have provided.