I’m using a toon-shading style and trying to render only a shade section. But I don’t know how. I don’t want to render a white section (in pic 1) and I only want to render a purple section (pic2)
You’ll have to use eevee and the shader to rgb node to do this. It converts the shading on the object into a texture that can be connected to the factor of a mix shader node and used to blend between two shaders (black in the texture for the shader in the first slot of the mix shader node, white for the shader in the second slot). You’ll then have to use the backfacing output of the geometry node and another mix shader to erase the backside of the object. Just make sure you set the blend mode on the shader to alpha blend so that the transparency will work:
Edit: I just realized that you don’t need to add the second mix shader and geometry node if you just uncheck the “Show backface” option in the shader settings section.