active blog link help??

Hello all, am very very new to code..although I have bought a customised template from Themeforest which I am very pleased with and I am managing to edit most things ok..whew! Apart from: there is a section called blog in the menu items and a blog post page, which, has been designed to look as though I can have a blog stream coming to my site but there doesnt seem to be any code for it. It is just css and html code. I would like to be able to edit my blog and for it to appear in my blog section on my website. The author said this is possible although I will have to change the theme of the blog to be like my website..does anyone know how I can do this please? The theme of the website is called Agensi. https://themeforest.net/item/agensi/93296

If anyone could give me an idea I would be very grateful..I think wordpress is great..am wondering if I should have just gone along with the blog route in the first place but the website has portfolios etc and is more intune with what I need..any ideas welcome..thank you forum.