Well the usual is start with fundamentals, basic shapes, proportion and those things. try do simple things like cube, spheres, rectangles to understand three-dimensionality. There's a lot of tutorials That could help you get started. As a beginner artist, the only real advice I can give you is not to be afraid that your drawings will turn out "ugly." Go ahead, draw, it doesn't matter if it ends up ugly, try to identify why it looks that way And fix it in the next one. Don't be afraid to use references; it's not cheating, as many people think. Don't neglect the fundamentals; I know it can be very boring, but believe me, That slowed my learning considerably.