Help a newbie understand recent update?

Hi there! First let me state that I hope I'm posting in the right place, and I apologize if I'm not.

I know the game was updated some time ago, I only started playing in December. I have two characters, mine: the mayor and then my little brothers character. I never play with my brothers but today I lost my shovel in a game with a camper and needed to borrow his, so I switched to his. He has a feature in his home that I don't have that makes editing homes insanely easier! I thought maybe somehing updated again while switching users, so I went back to mine and it isn't there. What gives?

You have to purchase the secret storage from Tom Nook first

yeah, homes have been updated! you can now purchase a secret storage room for your home.
once you have it, return to nook's or w/e his home design place is called, and you'll be introduced to a new otter! I forgot her name already fml
she'll teach you how to move furniture around now w the new feature

it cost hella bell-a

To be specific, the option to purchase the secret storage will be unlocked once you have a second floor.

Wow! My brother never mentioned that to me at all. Thanks everyone!!!!