Never don't trust a translator

Many years ago I received a friendship request on Facebook, from an American guy. I was glad that I would be able to tried try my English with someone who is a native.
I wrote to him in the chat :
Hello
He replied back :
What's up?
I didn't understand what that meant, because everything I knew about English was what I had learned at school. consequently I had taken that phrase into a translator and I got at a meaning of something like "What do you want?". In my tongue and even the in English, I think, when you say to someone "Hi" and he replay "What do you want" that is obviously rude, and seems like he won't keep talking with you.
That really disturbed/angered me, and I said to myself, what's wrong with this man? So then I replied "go to hell" and immediately blocked him.
What I am trying to say is all translate softwares are not efficient, and always make people make mistakes and misunderstanding ,like what happened to me.

Notes:

1.You have a few run-on sentences, so you might want to break them down, or use more commas.

2. Reply=replied. Replayed is to play again when talking about music or videos.

Have a good day :)