Slow down. Take a deep breath.
You're an INTERN. Use this opportunity to learn as much about this company's environment as possible instead of focusing on a deliverable. It simply makes no sense that you'll be solely responsiblesolely responsible for a productionproduction component. If you are, then the company is garbage and ran by morons. If I was a client of that company and I found out about it, I would drop that company in a heartbeat.
Take your time and digest what is happening. Why is a temporary INTERN being responsible for something like this? How are they ramping you up? How do they prevent catastrophic damage done by someone that is incompetent?
And go back to working normal hours. If they complain about you not working "hard enough", ask them what exactly does that mean? Ask for help to learn.
Don't waste your internship by grinding out ridiculous OT hours. It isn't going to help you, and the company is outright abusing you at that point.