how to get SILK ? whether it can be to mine the cpu ?
You can buy Silkcoin here:
https://poloniex.com/exchange#btc_silkAnd then move them to Bittrex and on 17th of September they will be swapped to Silk. You can't mine Silkcoin or Silk in the future, thats done already.
But Polo is delisting Silk today right? So between today and 17th there is no way to buy more.