TypeScript is definitely awesome. Before TypeScript, I would make sure you have a good background in component based design. You are no longer writing a webpage directly. You are writing a program that writes a webpage through transpiling.
I didn't spend as much time on TypeScript as I did on functional programming principles:
And went straight to fp-ts and io-ts where I focus my efforts.
If you are interested in how TypeScript actually works without a background in writing compilers, prepare to enter the Thunderdome. You will be building a compiler, a series of functions that need to run quick and meet a ton of specific unit tests: