1) The flat style used to be popular on the back of stuffing bags. Later they did more challenging ones. Try searching for "easy" patterns. Or use art references where you draw things by assembling geometric shapes.

2) To practice for the more elaborate models, I suggest:

https://mspremiseconclusion.com/2010/03/14/the-ideal-crochet-sphere/

https://www.ravelry.com/patterns/library/ideal-sphere

Add two small triangles for ears: you have a cat.

Add two long floppy triangles for ears: you have a dog.

Add two half-circles for ears: you have a bear, tiger, or lion.

Fill with a bag of sand, rice, polybeans, etc. and you have a stress ball or juggling ball.

This poem has links to hyperbolic crochet, which sounds difficult but is actually quite simple:
https://ysabetwordsmith.dreamwidth.org/11308073.html