1099k question, I have a 1099k from paypal that is what i won on casino online. How can I offset with my losses like I used to with w2g, where do I post? HELP

I have been playing on a casino website called chumba casino. It does everything through paypal.  You purchase through there and you cash out through there. I am used to dealing with w2g's and the losses that you can put in.  I have never had a 1099k before and I am wondering where do I post it and can I enter my losses and also which product do I need to purchase to enter this information?