I can't equip the hats, I got the requirements on the website (The mods)

When I try to put it into the slot I am not able to.

Closing as assumed resolved.

What mod loader?
What version of SimpleHats?
What version of Curios or Trinkets?
If you're trying to put them in the helmet slot instead of the Curios/Trinkets slots, you need to enable that in the config.

The newest for 1.20 is not meant to work with Curios 1.20.1, you need to update SimpleHats to 1.20.1-0.2.2

I am using Forge Minecraft as launcher, as for the version I am using the newest for 1.20. I am using Curios 5.3.5+1.20.1,

It doesnt work in the cosmetics slot either.

Also, I am using it on an aternos server but it isnt working in singleplayer either