how do browsers runs javascript? can i get a direct dissassembly to understand the underlining mechinism, how every line is parsed and compiled?

how do browsers runs javascript? can i get a direct dissassembly to understand the underlining mechinism, how every line is parsed and compiled?

Good day everyone!! I have been playing around with Javascript for some time and then i got curious on exactly how Does the java script runs in the browser. Is there like a GDB(a debuggers which shows every step of execution, states and also show assembly for c/c++ programs) for java script that would show the fundamental mechanism, states and steps browsers take to run Javascript at run time. I wish to develop a deeper understanding of web technologies and Javascript by understanding there underlining mechanism of there interpreters.

I am kinda expecting a debugger like interface that is showing us the execution of each line and i can interact with each of the variables and look there states.