Why does God ask to kill animals as sacrifices and offerings for sin?
The Bible describes in great detail the instructions for animal donations on the altar.
A person in the modern world sincerely does not understand why God can be pleased with the killing of innocent animals in order to propitiate God for human sins.
As early as the beginning of the Bible, we see that animal sacrifice was a human initiative. Cain and Abel decided to bring some sacrifices without God asking for those.