You need to go and download the latest version of Bitcoin Core from
their website.
You'll also need to read their
Requirements and Warnings page, which says, among other things, that you should have over 125GB of disk space, that some antiviruses might quarantine parts of the blockchain making it harder to run and that some internet providers might charge you for the extra bandwidth. Make sure you're prepared.
EDIT: I see that Digitalocean is a cloud computing service, so some of the notes about your internet will not matter.