So a few days ago I was watching blender guru's doughnut video. I found out that that was made in 2016 and that his was working differently. On his, the selected part came out when he set the offset to 1. With mine, it just moves the selected part into the centre of the doughnut. Can someone help
clearcoat = 1
clearcoat roughness = 0
If your using the principled shader (which is a good choice for a donut, I would recommend it), then you can turn on clearcoat, and set clearcoat roughness to 0. This should give you a glossy finish on top of your donut. I don't know if I have seen the tutorial you are talking about, but I think this is the desired effect.
Also, have you tried the blender from 2016? Older versions can be downloaded here: https://download.blender.org/release/