I can only recommend "The science of Interstellar" book as a great companion to the movie, explaining the physics side of it. As for Interstellar itself, I watched it the year it came out and I thought it was a pretty cool science-fiction movie. I rewatched it last year sometime after my father died of covid and I appreciated it from a whole different angle. Suffice to say, I don't remember the last time I cried watching a movie.