Need help about the light novel

I really enjoy this series but I usually don't have time to read manga because of my work, so I mostly just watch the episodes of anime. However, this time, instead of just quickly finishing something I want to learn more about this series that I really like. But I have a problem: I don't know where to read light novels online. Also, from what I've seen, people can find the novels directly as pdfs Moreover I dont know what it's like to read a light novel, even the simplest things like who wrote the text or to whom it was written. Any help would make this old man very happy.Good evening.