I never code in all of the 5 language before and never heard the name of them expect prolog so pleases help me to choose?
In the intro video of mindshifting may, Erik gives a great overview for all the languages available.
Of particular interest will be the last section, where I am suggesting what language to choose based on your interests: It's Mindshifting May! - YouTube
Is it also possible to get a badge by completing 5 exercises from different languages? For example: 3 from Prolog, 2 from Unison?
Yes, that should work