She deffinately was not chosen as heptopods do not have a choice

So many questions!
It's difficult to learn anything new without humility. The newer and stranger, more humility. And I don't think she was ready to teach (and don't we see her teaching later, and publishing a book?) until she had really learned it.

Imagine that.

I think you have a crossed wire somewhere.
It is clear from the plot that people at the other locations are trying to decode the language as well - hence the sequence about "offer weapon" v "use weapon", the other nations breaking off communication and the Russians assassinating their language expert.

I didn't know the book title was different but I can totally see why Story of Your Life won't work as a sci fi movie title I was thinking something like "Advent"

The title was supposed to match the one for the source material, "Story of Your Life." It was changed because the producers thought they'd make more money overplaying the Aliens aspect. I think they thought that people would think it was another alien invasion blockbuster (when it is anything but).
I find the title to be a betrayal of the source material, which is by the way far superior to the movie.
You can read it for free here:
https://libraryqtlpitkix.onion.link/library/Fiction/Ted Chiang - Story of Your Life.pdf
Go Colorado Buffaloes! The Pac-12 Football Cinderella story!

Perhaps the title had more meaning of where Louise ended up rather than the aliens arriving.