Most hosts provide the CP liscense. Cpanel Liscences are normally 35+ more than the Plesk/Ensim ones since of the price.
Mosts hosts normally install everything for you for the first time so that everything is ready to go ASAP.
You reall need to just know how to fix problems, setup accounts, ssh, secuirty updates, patches, upgrades, ips, etc, etc, etc. If you don't know that much I would suggest getting a managed server (the host upgrades secuirty holes, pathches, etc for you). The price is a bit more expensive... but its worth the money.
email software and cpanel and its supporting components all come installed. You will manage the day to day tasks from the WHM. Of course, the WHM doesn't do everything and there are instances when you will need to ssh into the server to do things manually. If you are not sure, you can hire somebody to do the odd tasks for a pre-set monthly fee and then you can have peace of mind.