Ceph is a large beast. A pretty awesome and powerful one, but a beast at the least - you've been warned.
For a first time installation, go to the Ceph tab and follow the on-screen directions.
It's best to dedicate at least a 10Gbit link, on each node, to Ceph (since it will be replicating storage data from node to node). Meaning - create a dedicated interface with it's own VLAN and IP subnet to Ceph. (Read ‘Change the Ceph Network’ to find out why you want to do this right the first time)