There's a building that my family would always drive by, but never actually visit, that said "Pool" on the front window.
As a child I didn't know any other meanings of a "pool" other than a swimming pool, so naturally, I thought it was a pool for people to swim in. Whenever we drove past it, I would ask my parents if we could go to the pool place. They always said no and told me that children weren't allowed in there. I was always confused as to why I wouldn't be allowed to swim in a pool until I was an adult. So for a long time, I assumed the reason why pool halls didn't allow children was because everyone had to go naked to swim in the pool.
I used to think that the initials NYC stood for "nobody you're calling"
When i was little, i thought the reason why people from New York sounded so funny because they had a cold stuck in their throat all the time.
when i was young i used to think japan and china were the same country
i used to think France was in the united states
When I was younger ,I used to confuse Spain and Alsace
I thought Clydesdale was a place dreamed up by a little boy named Clyde.
My grandma grew up in Eastern Europe and she gave me some old money from her country from a time of hyperinflation where the values on the bills were in the hundreds-of-thousands, and she said that's how much a loaf of bread cost back then. I was super excited and thought I was rich because of how big the numbers on the bills were! I didn't understand why no one else didn't just hold onto their old money from that time and used it today to buy mansions. My dad had a hard time convincing me that money from that time can't be used anymore!
I used to think Asians who wore glasses were meant to be cross eyed, because of how they read and write backwards in languages like Hebrew, Arabic, Hindi, Urdu, etc!
I used to think all urban city life in England had to take place in London, and everywhere else was just beaches and countryside. Think of places like the Yorkshire Dales and the Peak District, for instance.