Hi i am seeing in alt coin section there will be stakes distributed and it is asking for Ethereum address which accepts ERC20 Token . I do understand ERC20 tokens are digital assets . How i can sell these tokens and get ether or other coins ?? Please help
Easy. You will find out on the market there will be a project (if there is one). Fill in the details of the contractual address. Send coins get the coin for which your token is traded. And then on the stock exchange at your request, you can do anything. Let's say buy bitcoin.
Full does not know how to work with a crypt 
On the forum on cryptocurrency 