Transaction fee subtracted from your amount automatically by bitcoin wallet. I don't manage it. Just set to automatic.
I can set it to zero, but I'm not sure when you will get transaction. Sometimes transactions with 0 fee  not executed at all.
Big fee because people mosly play with small amounts, so transaction has more inputs if you win.
Some people, in other section, offer to work with Doge to avoid this.  

Idk, maybe I should do it.