For a brief moment, we are going to assume you know nothing about what you just clicked on. There are a lot of resources that explain what cryptocurrency is. This page is here to walk you through the process of getting started and to show you what you can do afterward. Click the logo for each.
We don't suggest you get into this unless writing is already your thing and something you are going to do anyway. Steemit allows your to curate content and earn their coin which can be traded on any marketplace.
Once you have bought some crypto with USD, Changelly is the cheapest way to convert between the different types such as Ethereum, Litecoin, etc. Changelly does it the cheapest out of all of the exchanges out there.