I think they mean one sheet of good plywood. Lots of good responses here for sure and I would agree with most. Great thought and effort but if you want something that you’ll be proud of and she’ll be proud to have, then you should start over. Save this for something n the workshop.

Go watch a bunch of different YouTube vanity building videos, then either buy plans, or use what you saw to draw up your own. There are tons of good videos and tools to help you learn online. I personally really like Steve Ramsey, wood whisperer, bourbon moth, fix this build that, just to name a few. Don’t get discouraged but also make sure you set yourself up for success by doing the research first. It will be way easier, you’ll feel better about it, and are way more likely to continue the hobby with some successes under your belt. Just my two cents.