Hi as you said the main problem is thinking is a simple as see on videos that are very confusing, Blender is a complex software, and maybe you don't know the basics for such type of application, is a professional software, and it is fully of features not only the rendering that is a final step for any works, the complexity is in various knowledge and as for others modern path tracer they follow the same rules, Renderman used in movies for most of the VFX is an hardest software even than Blender. To have a nice render you need to take the time and don't give up, many tutorials was made from newbie that don't really understand what is the right way to teach. maybe if you have time start reading some book or get a look on online manual. There is many steps before you know how use it, such as for material physics, like the glass that react in different manner if the have the thickness or not, for metals and many of those now are more simpler with a new node implemented in various rendering engines, the Principled shader developed by Pixar and used in Blender and others path tracer such as AMD ProRender Vray etc. for any materials there is many parameter to tweaking, but anyway if you have time is free great application, and make awesome render.

Below the link to the manual for technical information
https://docs.blender.org/manual/en/latest/index.html

and here a video series for First Steps - Blender 2.80 Fundamentals
https://www.youtube.com/watch?v=MF1qEhBSfq4

A great community where people share and helps
https://blenderartists.org/