are they available? can they be installed through some package in raspian?
What type of camera are we talking about here?. 
The 5MP Raspberry PI Camera board module, attaches with a ribbon cable to the board.
Take a look here, it might help as there are several links!:
I’m not sure you understand. I’ve used the raspberry PI’s camera, with Raspbian for a number of years, with both PI1 and PI2. I am now trying out ubuntu-mate for my new RPI 3 and am happy with it, but can’t use the the camera.
There are other references in the forum where people are trying to make the raspicam work, but I have not seen any definitive solution. Here are a couple of other questions posted:
My intent is to install motion on Ubuntu-Mate. Motion is available for the RPI using Raspian via apt-get, and that can detect the built in camera. I’m interested in a way to install the same, but on Ubuntu-Mate instead.
Hi,
sorry I cannot really help you there as I don’t have a Raspi myself!. 
If you hold out long enough, someone on this forum may be able to help you.