Modern books don’t have Sparknotes or Cliffsnotes and no one I know reads what I like so when I’m finished with a book I am dying to talk about it or at least hear what others think about what I just read.
Amazon reviews are pathetic, not that I necessarily expected more.
Where do I go?
What kind of books do you like?
The last book I read was Will Save the Galaxy for Food by Yahtzee Croshaw. It had a twist ending that I haven’t figured out and want to hear other opinions. Goodreads has some reader input, but very little.
After a quick search, I found this read-along thread in a forum. You could try finding a partner(s) to read a book with you. It may take some time to find someone to read a specific book, or you could tag along with someone to read a book they’re reading.
Or you could post the book in the forum to see if there’s any interest. It seems like there’s some activity there. One review says there are 30 posts/day.
Here’s the list I got it from.
I also tried r/books on Reddit, but they didn’t have nice things to say about the book you just read. But if you posted something up about it, you never know.
Snark works its way pretty fast into just about any thread on reddit. 
It wasn’t really snark, but I take that back. I only searched on r/books. Searching the whole site gives another hit.
Here’s one in r/outerworlds, not much discussion but the OP could contact the poster there to see if they want to discuss it further.
The r/books post was just calling it a ‘low brow’ book. The comments were about quick reads.
https://old.reddit.com/r/books/comments/hyyeh3/what_is_your_favorite_low_brow_book/
Goodreads includes not only reviews but also groups and discussion threads.
Hey, I was actually friendly with Croshaw years ago on a message board forum, before he hit “fame”. I’ve not read his novels, though I played his older adventure games.
Is the book any good? I’ll read it if you say so and maybe discuss it with you after.