There are many things that you can do to earn cryptocurrency, but none of them are particularly easy. Some are downright not even profitable, and others are a waste of time.
Here are some activities that you can do for fun as a hobby in your spare time if you would like to experiment with earning some bitcoin, alt coins, and crypto for yourself.
You can buy Bitcoin, Ethereum, Litecoin, and Bitcoin Cash here:
https://www.coinbase.com/join
ou can sign up for Minergate here: https://minergate.com/reg