Aww I love the kitty!! Your style is so neat omg
Oekaki works relatively simple, it's the best I can describe it is: poor man's art program. You can layers to draw on, a couple of blending modes, usually the standard kind one would expect to find. Pencil, some stencil, pen, pen pressure, colro wheel etc.
swatch for color saving,scatter basically applies a scatteration affect to the brush you're using so say pencil is scatter 50 you'll see there's disfigurement.
smoothing is basically the stabilizer if your hands are like mine: shakier than an earth quake. color basically plaies the color you're using to the bruch, spacing is like... hm. It basically jsut rips the brush open, so if you did a round pencil 100% spacing you could so beaded necklaces and stuff. Textures are basically tiles stencils if you applied a masking layer.
One of the lovely oekaki mods made a guide for this sutff I'm sjut summign it up in a TLDR format:
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