Unreal.js change blueprint variable

I have a String and int variable in my actor and I want to use and modify them using my JavaScript Script.

Here is my little function.

var makeMove = function () {

var Chess = new Chess(/get fen from actor/);

var bestMove = minmaxRoot( /get depth from actor/ , Chess , true);

Chess.ugly_move(bestMove);

/update fen of actor/

};

The fen is string and depth is int.

Thank you for your help <3