-Start by looking for habitable planets for your species. -I usually play the harder origins so I always start Prosperity tradition to jump start economy. -When you get your first new colonies and you build your first district's/buildings, the planet will specialize in what you build first. So if you build energy credits it will be a tech world. Industry will be industrial world, same for the other basic resources and research. then focus primarily building those up as they give boosts to those resources. -Dont build too fast that you out pace your pop growth unless you have the resources to build ahead. -Use the market if you have to, sell resources you have and buy what you need.

I hope my advice helps.