It will be clutch slave cylinder.
As it sounds like they use a concentric slave cylinder – you have to do 100% of the labour also required to change the clutch – so unless the clutch is brand new (in which case, shoot the person that didnt do the slave cylinder!), then yes, it makes total sense to put a clutch in it too.
Flywheel – likely a dual mass flywheel. SOP would to replace it, but you can get away without depending on age/condition. More likely to be needed on a Diesel (more vibration nastiness to absorb).
You dont need any sort of specialist to do this work, its absolute bog basic stuff for any MOT & service place.