So implement four of them, and you will know them all! First Forth with indirect threaded code, second Forth with direct threaded code, third Forth with subroutine threaded code, and the final fourth with token threaded code.
I doubt you will want to code professionally in Forth unless you work on embedded, so the dialect you learn doesn't matter too much. But it is interesting to implement a small interpreter and play with it.
I was expecting to see FORTH in bare metal C or ASM.
There is a common myth about newbie programmers that FORTH is write-only and that you need to type everything in one line, without comments or function calls etc.
Writing forth is super easy especially if you have a stack machine at your disposal. For example when you are building your own virtual cpu/architecture with assembler and compiler.
It's more trivial than to understand any JavaScript framework lol
Research FORTH more guys - it doesn't need to be strange and hard :)