which npm libraries should I know if I want to start a web3 project?

I don't want to be rude but it is a bit of a weird question that would suggest that you're pretty new to the programming space?

I would suggest by first starting with understanding web3 and what it's all about, then find some problem or project that has a goal you want to achieve and then start working towards that goal. On the way you will most likely face issues you need to solve and then you can search npm packages to help you solve these specific issues.

I wish you luck though!

web3.js or ethers.js. These are the standard ones with a ton of support and tutorials, etc.