today is exactly the first month I started learning programming. But, I have always wondered, how is a language created? and why people willingly painstakingly learn new language when its not widely used?

Because they have different use cases. Read about compilation or interpreting cycle of any language. And that how it's created.

People invent new languages because they dont like the ones they are using. Brad Cox invented Objective-C by writing a preprocessor for C to make it behave like Smalltalk.
Bjarne Stroustrup invented C++ by writing a preprocessor for C to make it behave like Simula.