If you want to learn about blockchain technology through building one (albeit a simplified one!), here are some good articles:
As for building an application that uses a blockchain, there are so many emerging options but I'd say the best for 'getting started' is definitely Ethereum. It is (relatively) mature and has a large community behind it.
If you're looking for an introduction to writing decentralised apps with Ethereum smart contracts I'm writing a blog series on exactly that! Check it out: blog.jaak.io/crossing-over-to-web3-an-introductio…