To use MySQL Fabric, you must have a set of MySQL server instances running MySQL 5.6.10 or higher. You need one server for the backing store and at least one server to add to a group. For replication features of Fabric, you should have a replication topology of a master and at least one slave. For sharding features of Fabric, you should have the number of servers corresponding to the depth of the shards (the number of segments).
For instructions on how to download and install MySQL server, see the online MySQL reference manual (Installing and Upgrading MySQL).