Hi,
1. We shall draw lots every day and thus decide who is to die.
What is the meaning of the words in bold? There are various ways to draw lots. eg Put several white balls and one black ball in a bag. Each person puts in his hand and takes out one ball. The person who takes out (ie draws) the white ball, in your example, is the one who will be killed.
2. Our herds are being torn apart by pain and despair.
What is the meaning of the words in bold? I'm not sure why you are asking. Surely you know, for example, the meaning of 'pain'?
A more immediate concern about your sentence is that 'herds' refers to groups of animals, while the phrases 'torn apart' and 'pain and suffering' are usually related to people.
Best wishes, Clive