In order to build, you will require cross-compiled build tools for the i386 platform. For this, you can refer to this excellent article on OSDev Wiki. (Note that you don't need a cross-compiled GDB if your computer architecture is x86_64).
In order to run, install qemu-system-x86_64.
$ make disk -j$(nproc)
$ make run
To run with GDB debugging
$ make debug