How do I uninstall plugins / mods?

I saw a thread somewhere saying "go to https://aternos.org/files/mods and uninstall the mods you don't want" but when I go there, I'm told that my access is denied. I'm not a guest; I am the operator and admin of the server, and I one other person have access to the ability to start the server, but it still tells me that my access is denied.

By the way, that account and this account are different; I couldn't sign in with gmail on the forums but I could setting up the server, so they're not the same.

nevermind? It's the plugins folder... I found it. I wonder why I was pointed to mods and not plugins...