Hi edilsoncs! Answers for you below:
In combat effect:
The damage reduced in combat is 5. And it said that I can use in up to 3 units.
May I distribute 5 in 3 units or heal 3 units with 5 ??
When the end of combat occurs, you add up all of your attack and defense. You would then also take into account the reduction in damage and subtract that from the damage total.
Out of Combat effect:
the question is similar before.
I Heal five distributed in 2 units or 2 units are heal 5??
I'm not quite sure I understand your question, though the effect of healing is the same as above.
I hope these helped. If you have any other questions, let us know!