The main leap imo is you need to think about the project as a whole, not just your piece. You need to "see around corners" to identify anything (even if it's no

The main leap imo is you need to think about the project as a whole, not just your piece. You need to "see around corners" to identify anything (even if it's not technically under your purview) that could block the project, then raise the biggest stink necessary to fix it before it becomes a problem. Some lead devs do this naturally, some never seem to be able to. Do not let your first project with a new company fail. You won't recover from that, even if it's not your fault in any way. Succeed and you will become known as a person who gets things done. Also be a mentor to the other devs. But I assume you're already doing that if they hired you as a lead and based on your ideas.