Fire and Blood by GRRM. Despite the series being unfinished and the show ending the way it did, I still love the series. Fire and Blood delved more into the Targaryens and their familial history, which were my favorite bits in the series. Having been laid off and stuck at home, I read the 700+ book in 3 days. It got me back into my love of reading, which had sadly fallen to the side due to work stress and some mysterious health issues that had been popping up. So it both kickstarted my reading during the pandemic and after!
The Dear America series. I DEVOURED those books growing up. I loved the ribbons as bookmarks and the different periods in history.
Charlie and the Chocolate Factory was a big one as well. Rented it so much from the school library the librarians actually refused to lend it to me one time because other kids wanted a turn with it
And finally the Harry Potter series. I was the same age as the titular character when the first book released so it was like we grew up together in a way. I’m doing a reread of the series right now and I almost forgot how big of an impact it had on me growing up