Critique: Needing Advice on Shading

[Raydrawsx]

Hello there, I am looking for advice on how to make my shading more pleasing to the eye in terms of the colors being cohesive and the shading as realistic as a 2D drawing of a furry can be (sorry if that doesn't make any sense). Any resources for reading or videos, or more direct tips on the peices provided below would really help thank you for your time!

 

[BSporn]

For the bottom picture. The most immediate thing to me is that the glowy bottles are casting light onto all the characters, but not the environment at all. Like they're bright enough to be blowing out the colours into white on the characters it should be doing the same on the table right next to him.

Give me a chance to get home and I'll try and come up with something more in depth for you.