Hi @尔德_王 I’m sorry your experience has been challenging.
I know the channels can be a bit tricky to navigate at first. But it’s actually quite easy to manage the channels and categories if you are an admin. For channels, simply go to the channel and click the channel name and it will give you the channel settings (you can delete the channel at the bottom). For categories, go to the category you want to edit/ remove, and click the admin wrench icon in the top right corner to get the catergory admin settings. From there you can delete the category witth the button at the bottom of the category settings screen.