I actually came across a spoiler for the I Am Legend book years ago, so it wasn’t a total surprise. Though either the spoiler had it partly wrong or my memory of it wasn’t fully accurate so there were still some surprises. Did you read through the short stories as well?
I finished the short stories in my copy of I Am Legend by Richard Matheson. Some of them haven’t aged that well but overall I found most of them enjoyable.
I read Piranesi by Susanna Clarke. This book was absolutely amazing. If you want a short, atmospheric fantasy I highly recommend. I think this is a book I’ll return to routinely.
Now I’m reading Educated by Tara Westover. It’s a memoir about her growing up in a survivalist family in rural Idaho. She was not enrolled in school and didn’t even have a birth certificate for many years. I’m not very far in yet but it is fascinating and very easy to read.