How do I build the "To add content" page of a responsive website

Context: Ok so I am building a website for a friend. Hes a designer with a high need to daily include his projects (images and text).

Problem: Ok so I know pretty much how to code in html/css/javascript a front end responsive website, that is the easy part for me, the hard one is the content page. I've never done it so I don't know the best way. A page that he goes daily put a new project, new images, formatted text (A like a blog). But since he doesn't know anything about coding and front end, it has to be simple enough for him to understand.

Resources: I made several searches and found some websites that allow custom templates with content, one of them standing is wordPress (haven't used it for years). I am currently abusing tumblr for that matter, but their support is quite bad. Should I use one, should I buy a host like bluehost and create my self one, what you guys recommend? I tried google it but perhaps I am not doing it the right way since I am not finding any answer to my problem.