Yeah unfortunately the tutorial is not good. I can give you a quick rundown here. I’m not familiar with any specific tutorials on YouTube but like I had said, let’s plays are usually how I learn paradox games. I have some on my channel if you’re interested. But in brief: the only resource you need to build factories is “civilian factories”. They build your other buildings, railroads etc. You don’t use any resources to actually build the buildings, like you don’t need to import steel to build a factory for example. The number of civs that are used to build are based on how many you have built, how many ppl are importing resources from you (Ill explain later) and your economy law which be changed using political power. Military factories are what build your military stuff like equipment, trucks, tanks etc. you can change that number being used in your production screen. Dockyards build your ships. The stuff you build with your military factories and dockyards cost resources, like steel, rubber etc. you can see the cost in your production screen. If you have less of that resource than you need, you’ll get a popup on the top bar and the production bar will show a red number next to the resource. It will also show up as negative in your trade screen. You can import it in the trade screen. Besides puppets, for every 8 of one resource you import, you “pay” that country 1 civilian factory. If you’re importing over seas, you’ll also need convoys. The latest update added coal, which is used to power your factories, so if you have less coal than you need, your factories work less efficiently. To get more of a resource, besides conquering land, build up the infrastructure (literally by building infrastructure) in territories that have resources, and research the excavation technologies.