The video "But how does bitcoin actually work?" by Grant Sanderson (a.k.a 3Blue1Brown) is a great visual introduction to Blockchains and their inner workings.
In it, Grant builds up the intuition behind Blockchains by slowly introducing and explaining the individual constituents and the math governing them and the whole system. Once you've watched it you should have a solid understanding how real world projects like Bitcoin, Ethereum or Cosmos work behind the scenes.
- Grant Sanderson