Life, Death And The In Between

I have always wondered where the concept of Life and Death began, as a catholic, I understand the basics of Gods creation and the story of Adam and Eve, however for me these basics are not enough, I want to know who decided we will live to eventually die? and why?, who decided we would have two legs?, two arms? four fingers and a thumb?, where did the ability to walk begin?, who created disease?,who decided we would live in houses? who decided what houses would look like?. Who created a male and female?, the words mum and dad?, gran and grandad?, who created words?, I could go on all night, theres so many questions I would like answers to however i do not believe i understand the language of the bible enough to get some answers, I want to hear opinions i want to know if anyone else thinks about these things and the most important question id like to ask is whats the reason for our eventual death?.