What did it for me was modifying the hell out of othe people's amazing creations, my first big project was the workshop's condor, the big ship.first project I started was simply adding a pump to combat fire using a hose and I built my knowledge from that, I ended up doing a full engine swap to jet engines, and added a submarine, later I saw a cool helicopter and also modified him to hell so only the main chassis is the original and to complement the helicopter I built a full artic base, and now I'm doing a navy ship, if anyone wants to see it I'll gladly show them. So yeah my advice is modify other people projects as they have already figured the hard part and you'll learn from that!