Can some mods not work with each other?

Hi everyone, I have a question here and am I’m very new to Minecraft :)

I downloaded Minecraft a few days ago and installed two mods/ extensions but they won’t work with each other. I have a shaders pack on and the controller mod from forge because playing with a controller is much easier for me personally.

They work fine by themselves but if I have one on, the other won’t work. I have the latest update to Minecraft and both mods are for this version as well (1.21.) any tips or suggestions would be appreciated, thank you :)