As a person who's read widely in the English literary canon, I have to say, I thought the Guardian's top 100 was a reasonably good list.
Not perfect, of course, never perfect.
But a reader of English novels could do a *lot* worse than to start there.
I've read ~55 of those books. I am, of course, a total book dork, among my other dorkeries.
https://www.theguardian.com/books/ng-interactive/2026/may/12/the-100-best-novels-of-all-time
EDIT: Apologies, didn't realize it was paywalled. Here: https://www.reddit.com/r/TrueLit/comments/1e1m7rg/the_100_best_books_of_the_21st_century/