Need help decoding something but don't know how !

Your code is wrong, it's not "x}ti" in the middle, it's "xcti".

A hint ? This and also this.

Or you can decode your code on dcode and enter the code and put "4" in "knowing the shift/connaissant le décalage" (hence the +4 at the end of your code).Only the letters matter. It gives "Quel$est$ton$type$de$biere$preferee", aka "Quel est ton type de bière préférée ?". The letter "Q" +4 in the alphabet = U (QrstU), etc.