Someone do the shading

this is my first ever pixel art drawing, and as you can see im not that good with painting, so someone could do the shading of this character, so i can take it as a refference? Sorry for my bad english, im form south america, Brasil!

The shadow can be done in several ways. There is no single method or form. First thing is to define where the ambient light source is coming from. With this you can study how the shadow behaves. Below are some examples. Get references from the internet of photos that have the same configuration as your composition. It will be easier to do the shadows later!

thx for the help man, have a great day!