help with details if possible

[alpaca]

it is so hard to transfer some units of kingdom's byzantium to original m2? :((((

For a complete newbie, yes. Check the links section for more info. The tutorials you're looking for are things like adding new units, adding new models, etc.
You need to edit export_descr_unit.txt, battle_models.modeldb and export_units.txt at the very least. If you also want the skins etc. to actually show up you might also want to copy them over, or adjust the links in the modeldb.

Welcome to the world of modding (and the forums, of course)

[byzan]

thx a lot guys :) i'll try my luck :)