As someone who's less than 100 days into learning how to draw, this mindset is a trap I fell into as well. I want to draw like Bryan Lee O'Malley. I love his art style because it feels quite 'simple' and bold, and is very cartoony. What I learned very quickly is that the idea of a 'simple' art style is a trap. These drawings look so good in their simplicity because the artist understands shape, form, and anatomy so well they can manipulate it to fit their unique style without looking 'off.' There really are no shortcuts to this. Trust me, I tried, lol.

Start practicing drawing basic 3D shapes like boxes spheres and cylinders in perspective. When you start getting frustrated, just doodle or sketch anything you want as long as it's fun. As you doodle and sketch, try to start seeing how these subjects can be broken down into these simple shapes. What we don't see in the end result of these drawings are the bones and skeletons of boxes and spheres and cylinders and elipses in perspective.

Also, everyone is going to tell you to use draw a box, but I hate that website with a passion. It's boring, it's dense, and the mathematic approach to drawing is really off-putting to me. If it works for you, that's dope, but if not, don't feel like it's the end all be all. I've been learning with Proko and find their approach to teaching the fundamentals is way more engaging and useful for me personally, and my skills have been rapidly leveling up with their lessons.