How do you properly get started and improve in using arduino/ making cool stuff with arduino and other microcontrollers or raspberry pi etc

I'm a beginner to using arduino/ electronics/ tinkering or whatever it's usually called and I've made 2 simple projects in the span of about 3 weeks. When I look at what other people make like flight computers for model rockets,PCBs, AI controlled robots and life sized animatronics, I wonder how these people started out and progressed.

Tldr: If you're very experienced in this field, may I know how you started and progressed in detail?

For example like you made 10 projects with the components in the arduino starter kit then started using things like raspberry pi and esp32 then started to learn soldering etc etc (sorry I don't know enough to make a good example)

Sorry if this was long, would love to hear everyone's input :)