boot - Installing Debian on my macbook air

I want to install Debian on my macbook air 13" from 2011. I'm following this tutorial: https://wiki.debian.org/MacBookAir4%2C2Testimonial

It starts by telling me to use bootcamp on OS X. I don't have OS X anymore, I'm using windows 8.1 on my macbook. I have 2 partitions: Bootcamp (C) and HD (D). I want to install it in the second partition (HD), but only in a piece of it. Then, I want to put the rest of HD together with Bootcamp, to form a greater partition.

So, this is the idea:

Bootcamp: 64Gb HD: 64Gb

I want to use 28Gb from HD to Debian and merge the another 28Gb with Bootcamp to form a partition with 100Gb.

First of all, can I just do it using the disk management tool from microsoft? I would Shrink the size of HD, to create a new partition. Then the idea was to install Debian in the new partition and merge the rest together. Is this easy to do?

The tutorial has this step:

I installed gdisk [1] and added a linux partition out of the free space, not creating any file system.

So I can't use the disk management tool from microsoft? How do I create a partition with gdisk? Is it before or after shrinking the volume of HD?

I also made sure the latest firmware update (2.2 at the time) and OS X update (10.7.2 at the time) were applied, which they were from the factory.

I think my firmware is 2.2, but I don't have OS X anymore. How do I verify it?

I also made sure the latest firmware update (2.2 at the time) and OS X update (10.7.2 at the time) were applied, which they were from the factory.

I don't have OS X, so I don't have this 'dd', I think. Can I just use a normal program to create a bootable pen drive?

I also prepared a second usb stick for firmware from [3], but in the end it did not work automatically (because of using double usb sticks?) and I copied the firmware in place manually. The files needed are brcm/bcm43xx-0.fw and brcm/bcm43xx_hdr-0.fw from the package firmware-brcm80211_0.28+squeeze1_all.deb

how will I extract the files from firmware-brcm80211_0.28+squeeze1_all.deb?

Also, what is this "GRUB installation", and where do I install it?