Dear gurus, I am newcomer here. Today I have started with SW2021. I am very sorry for the silly question. The HELP says that MEASURE TOOL - Measures distance, angle, and radius in sketches, 3D models, assemblies, or drawings. Also measures the size of and between lines, points, surfaces, and planes. But I can not see how to measure angles between lines and angles between planes in 3d part/assembly modeling
I know good enough to measure angles in physical manner. I need to measure angles in 3d models of parts and assemblies.
go to EVALUATE tab.
pick measure tool
left click on two surfaces.
If two surfaces are 0 degrees SW will say two surfaces are parallel or 180 degrees if there is a difference of 0.009 and bellow, else it will return the actual degrees between two surfaces
Examples
parallel

not parallel

I hope i understand your question correctly and my answer help you out.
If you need something more please feel free to ask
Thank you very much, Ioannis! The important was LEFT click.
I did it, I have received a lot of good stuff, including the angle.
