Minecraft tektobia shader?

I've installed the tektobia modpack from the twitch launcher, but when I play games, I see everything darker and in 3D.

What can that be and what is it called?

That will be the modpack what you have installed? Or do you also use a shader?

Ne do not have shaders do not even know how to install it (Sorry, it got on it)

You need to use mods and shaders to be able to install some other stuff before you look at youtube, there are a lot of guides for that

You also need to install optifine then you can also add a shader.

Press Escape, go to Mods, and then do the shader out.