You will find a variety of brushes with different effects such as crayon ... You can also convert your 2D drawing into a 3D picture by editing it in Paint 3D. Go ahead and simply explore!

For a different effect why not use a toothbrush? You can use this to sprinkle paint onto your painting. So I'm going to dab it here in the green paint… and then - this is a bit messy - sprinkle ...