1. Why do we need blockchain?
Bitcoin, Ethereum, etc are not just coins but the core of decentralization, helping millions of people realize the concept of ownership. Watch: https://youtu.be/lyIy4AxmPIU
2. How does the Blockchain work?
Understand everything in blockchain starting from scratch — SHA256, Hashing, mining, decentralization, calculations, the math behind it, how the chain works, etc.