Selling home made items

This is going to be lengthy but I’m genuinely curious how you gals/ghouls get started with creating art/home made crafts such as things w a cricuit etc ... the beginning processes and then how to begin selling? Obviously the first step is getting the hang of what you’re doing and stuff but what I’m confused about is how people get custom templates or molds (things of that nature) are they from previous ideas or ideas you come up with and have made into these things? And how do you manage to sell things that may have already been done without it being like copyright and such? I’m so fascinated by artwork and crafts and want to just start a hobby clearly but I want to do things with originality not just copy’s of what other people have thought of.. thanks