Q 2: One day,
I saw dogs attacking a female sheep but did not kill it, so I killed the dogs. I do not know the owner of these sheep. I carried the attacked sheep to a nearby fence and left. Please, tell me the ruling on this act. May Allah reward you with the best!
If the reality is as you have mentioned, you did well and are free from sin. You saved your brother's property from destruction, thus reward is expected in sha’a-Allah (if Allah wills) for that.
May Allah grant us success. May peace and blessings of Allah be upon our Prophet Muhammad, his family and Companions!