I'm going to recommend a book and then recommend other things (another book, TV show/mini-series, movie, etc) that someone who liked that book may enjoy (also works in reverse -- if you've already seen the movie I recommend but not read the book that prompted the recommendation, maybe give the book a try).
If you liked...
Eleanor & Park
by Rainbow Rowell
Book: Everything Beautiful by Simmone Howell
Show: My Mad Fat Diary
Why: Once again, going with the weight theme here... The main character of this show is overweight. She's dealing with mental health issues, family issues, she's confident in some ways and insecure in others. Her story is funny and it's heartbreaking and it's about friendship and love and acceptance and getting better -- and, again, she gets a love story. Plus! If you liked that Eleanor & Park was set in the 80's, this show is set in the 90's.
Movie: Never Been Kissed
OR if you liked...
by Kody Keplinger
Why: It has a lot of similarities to The Duff, like insecurity and self-confidence, like sexuality, like self-respect... I dunno, I just think they have a lot of overlapping themes but it's presented in a slightly more comedic way in Awkward. (Just a note though: the first season or two were definitely better, it lost a lot of its charm later on).
Movie: Ten Inch Hero
Why: Well, The Duff has its own movie so that would've been the obvious rec (except they do change a lot of the story)... But yeah, Ten Inch Hero (although, this rec really depends on your age) -- the characters are in their 20's and it's about friendship and realising you need to love and accept yourself and it's just really good and sweet and funny.
***I grouped those two together because they have similar subject matter so the recs for those two books are interchangeable***
If you liked...
Code Name Verity
by Elizabeth Wein
Book: The Book Thief by Markus Zusak
Why: Heartbreaking WW2 story, beautiful writing. Female main character and the things she goes through and losses she experiences. Any hints of romance are only minor sub-plots, friendship and family are the heart of the stories.
Or if you liked...
Between Shades of Gray
by Ruta Sepetys
Book: The Bronze Horseman by Paullina Simons
Movie: Lore (based on a book, is on Netflix)
Why: This movie is subtitled but worth watching. It's about a young German girl and her siblings just as the war is coming to an end -- her father was a Nazi and it's about her disillusionment, her journey of coming to terms with the awful things he had done while struggling to get herself and her siblings to the safety of her grandmother. Again, it's a young girl trying to survive the consequences of war and a different side to the story.
***again, with those, similar subject matter so the recommendations are kind of interchangeable***
If you liked...
The Fault in Our Stars
by John Green
Book: Me, Earl, & the Dying Girl by Jesse Andrews
Why: I admit, I wasn't really a fan of this book. Strange way to start a recommendation, I know, but I've also seen mostly glowing reviews of the book from people on Goodreads and booktube and blogs...so, while it wasn't exactly my kind of thing, I do think it's one that might work for fans of TFiOS.
Show: Red Band Society
Movie: Keith (link to the trailer, but the trailer basically spoils the movie, jsyk)
If you liked
Throne of Glass
by Sarah J Maas
Book: The Lumatere Chronicles by Melina Marchetta
Why: Well written high fantasy with strong female characters and they're both about people who have had their kingdoms taken from them/taken over and their fight to get it back.
Why: Legend of the Seeker because it's an epic fantasy series, it has strong female characters and magic and all that good stuff. Reign is a bit more grounded in reality as it's an attempt at making a show about Mary Queen of Scots (*is Scottish, is laughing*) but watching it really does feel more like watching a fictional fantasy show -- they've added subtle supernatural elements and it's not historically accurate and the costumes are incredibly pretty but laughably wrong...so yeah, female queen and her group of friends and their lives at court and all that good stuff.
If you liked...
The Iron King
by Julie Kagawa
Book: A Court of Thorns and Roses by Sarah J. Maas
Show: Lost Girl
Why: Again, about fae. This one is actually about a succubus and her human best friend/sidekick solving fae crime (there's more to it than that, and there's a larger fae story arc going on, but in the early seasons the episode arcs were mostly like them working on cases).
Why: While not about fae, both of these feature girls pulled from their own world into fantasy settings (in The 10th Kingdom, it's kind of Once Upon a Time-ish, where storybook characters are real...with Alice, it's an interesting take on Wonderland with a really adorable Hatter).
I have more of these written out, but I'll stop there.
If you'd like more of these posts or if there's a book/show/movie you want to see recommendations based on, just mention it in the comments (and what you want the theme of the recommendations to be, like similar subject matter, similar plot, similar atmosphere or relationships, etc.).