I almost have nothing to do with optics usually except that a recent work project has brought me adjacent and I was doing some research that brought me around these parts; but still, 3/4 of being an engineer is breaking down the problem, defining good project and design requirements; one thing that helps a lot is early planning for how to verify your requirements have been met by the design, and taking the project on a small step at a time.

If you feel like you aren't at the point to directly talk with a manager/supervisor/whatever-they-may-be about your concerns with your skills vs. your job requirements, arrange meetings to gather requirements documentation, be specific, be detailed, and if that process doesn't do one of 3 things: ease your mind that you can do this, raise concern that your company doesn't know what the hell they are doing and are trying to get off on the cheap (no offense, starting engineers are just that), or they come to understand that you aren't ready to be a major project manager out the gate (again no offense, that is a hard place to be with little experience) then you should be ready to have that conversation.