Midoriya Izuku was not weak, though his cute face and short figure may suggest otherwise.
He had a quirk, though he doesn't use it that often since his quirk is just 'Atomic Manipulation' which allows him to change and create anything he so desires. Which is honestly kind of like creative mode in Minecraft, if you asked his classmates. But since Izuku is a pacifist at heart, he only ever uses it to make mini figures of his childhood best friend, and that flatters and annoys said childhood friend, Bakugou Katsuki.
The quirk doctors had been baffled when his quirk was revealed, when he had turned the couches into a giant pile of books and the clock into a pizza -which was actually really tasty- when he got frustrated at a puzzle that his 4 year-old brain could simply not comprehend. His poor mother had walked into the living room and was met with a pizza on the wall and a shelf's worth of books.
When he first got his quirk, his control was atrocious and shaky, turning plates into balls of cheap china and pencils into a cube made of a mix of lead, wood, and eraser. It had been a nightmare for the whole neighbourhood, who had been mercilessly subjected to loud crashes and ear-piercing thuds.
Now he's an airheaded middle schooler who is only still alive because of Katsuki saving him from kidnappers and stray rabid dogs. Word had spread that he was actually quirkless, though that rumor had been completely rejected when someone had made fun of Katsuki for being friends with a supposed 'quirkless loser'. (Nobody even dared to look Izuku in the eye for 3 months straight after the incident, but they don't talk about that anymore.)
So there's that.