To download the source for the Linux kernel on a Red Hat based distro you'll need to use the tool
yum. This is equivalent to
apt-get. This tool needs to either be run using
sudo or to become the root user on the box.
$ yum install kernel-devel kernel-tools kernel-headers
The source will be installed here:
$ ls -l /usr/src/kernels/$(uname -r)
uname -r is the version of the kernel + architecture that you're using:
$ uname -r
This is the source for kernel version 3.13.9. The point release (the Fedora project adds patches to their kernel) which is represented by the
-100. The architecture is
x86_64, i.e. 64-bit.