Answer 1

There is a course on UDEMY for that: https://www.udemy.com/create-a-new-programming-language-from-scratch/

Here is a story about creating new language:
https://medium.freecodecamp.org/the-programming-language-pipeline-91d3f449c919

Someone did it before:
https://hackernoon.com/lets-build-a-programming-language-2612349105c6