Welcome to the forums!
TBT Bells (Just called "Bells" in your side bar, or if you click on your avatar on the tab at the top of the page), are a forum currency. They can be used for trading. For example, someone might trade forum currency (TBT) for in-game currency or in-game items. Someone also might trade forum currency (TBT) for forum collectibles (collectible images that are displayed under your name).
The
TBT Marketplace is for trading forum currency for forum collectibles.
If you're looking to trade forum currency or in-game items for other in-game items, you can do that in the
Nook's Cranny forum!
Happy to try and help if you have other questions!
How long have you been playing New Horizons? What other Nintendo games do you enjoy?
Hope you enjoy it here!
but why so complicated? XD I have been playing Animal Crossing New Horizons since August 
if he 
? XD
