I've got a board with a "HT68FB560" mcu but I don't really know where to start so........ I came here to ask you where should i begin from?
Do your home work, have you searched for info on the mcu (data sheet)?
Is the board a demo/development board?
Does the board have a programming or debug interface?
The mcu sounds like a 68000 derivative, is that correct?
If so, there should be freely available compilers linker and debug tools.
You will need the memory map for the board to be able to access/control the peripherals.
Search for any free drivers (source code) for the mcu/peripherals even if they are the wrong os, yiu can port them.