I'd suggest checking out online bookstores like Amazon. Sometimes, they have a wide range of light novels available for purchase or reading through their Kindle service. Also, keep an eye on fan forums and communities related to Cote, as members often share where they found the light novel.
You can often find 'cote light novels' in local bookstores. Some big chain bookstores usually have a section dedicated to light novels, and they might carry the 'cote' ones.
It depends on your familiarity with Japanese - inspired settings and some of the cultural nuances that might be present in the Cote light novel. But the language used is not overly complex most of the time. The story is told in a way that draws you in, so as long as you have basic reading skills, you should be able to follow along. Also, there are often translations available that are done in a way to make it easy for English - speaking readers to understand.
You can start by finding a reliable source to get the novel. Then, set aside dedicated time each day to read and focus on the story without distractions.
I'd suggest starting right after the point where the anime ended. But if you want a deeper dive into the story, beginning from the first volume would be great. It'll give you a more comprehensive understanding of the world and characters.