MyBB Community Forums

I have a category on my forum with multiple boards in it. I want to display a custom message that shows up before the list of board, and only shows up when viewing this one category.

How can I do this?

Thank you.

in the forum management section of the admin panel, each forum / category can be set with rules
though it is called rules, it can be any custom text. html code can be also used for it.

more details --> Forum Rules