Yes, the Life is Strange comic is official. It adheres to the established lore and characters of the franchise, providing an extension of the story in a sanctioned manner.
In most cases, the Life is Strange comic is regarded as canon. It provides additional depth and context to the main storyline, and is consistent with the established universe of the franchise.
Strange World isn't a comic. Usually, when we talk about Strange World, it refers to a particular fictional setting or story that isn't presented in the comic book format. Maybe it's a part of a broader multimedia franchise, but not a comic specifically.
In fact, 'Strange World' has its own unique story and concept that was developed independently and not adapted from a comic. The filmmakers came up with the idea and built the story from scratch.