I don't want to sound like an ass, but if you don't have the ability to use google or search the forums to find this answer yourself, you probably shouldn't be investing in crypto, as you'll need to do far more DD than this to properly invest in altcoins.  To answer your question, poloniex and bittrex are what you're looking for.  Kraken has left a lot of potential revenue on the table by not listing certain coins like NEM. Their loss.