What is life before life?
If you believe in karma, there's life before life and also life after life. This is a never-ending cycle where we experience sufferings repeatedly. Sure there are good moments in life, but those moments don't last long. Same goes to unbearable moments. Everything is constantly changing, every second, every millisecond, every units-smaller-than-that passes by without you even realising. Therefore, it's important to live in the present, do not hold on to the past and fantasize about the future. The life before or after life doesn't matter anymore, what's important is "now". Cherish every moment in your life, there's only one way to get out of this never-ending cycle of life full of sufferings.
If life is the existence of living things, then there were no living things before they existed.
If you mean life on earth, that can not be answered.
If you mean the existence of incorporeal souls/spitits/essences, different faiths have different answers but no one knows anything as fact. Many forms of major Asian religious beliefs include some form of reincarnation which is usually somewhat dependent on behavior in one or more previous lives. Many Christians believe that there is no such thing and the soul/spirit is created by G-d at conception or at least by birth. Most Muslims believe everyone's soul was created at the same time as that of the first man's soul. Some Jews believe that souls reside in a "guf" or "treasury of souls" in the garden of Eden before an angel puts it in a fetus/baby. The range in indigenous beliefs are quite broad and span from belief that a person has several types of souls with different origins to the idea that there is only one spirit and every person contains a small piece of it.
From a Christian perspective (specifically The Church of Jesus Christ of Latter-Day Saints):
Life before mortality consisted of a life with God. You learned that the purpose of life was to gain a body, experience trials to learn and grow, and to have your faith tested to see if you would rely on Jesus Christ.
In this, the so-called pre-mortal life, you developed your personality, the talents you have, and you prepared to come to earth where you would accomplish all you set out to do. You chose to follow Jesus Christ in coming here to mortality, and in choosing to follow Him again, you can return to live in the presence of God and enjoy all that He has.
Once life starts in a universe it is passed on source energy released seeks the most efficient use of itself this drives evolution , different energy forms , space , matter form most likely RNA formed a virus that eventually created DNA seeking more efficient use of energy then the first basic cell and it developed again seeking the most efficient use of energy , this early life may have survived in space at times before really taking hold on earth when conditions were perfect and our evolution began , eventually energy in this universe will reach entropy collapse and with a bounce the process will begin again .
Life must be operationally defined. Life is, however different forms of living organisms exist. Humans create paradoxical questions, much as existence after life, a proof exist as thought only, much as the freshman question on trees falling and do the make sound if no-one is there to here it, it and questions similar are language games, devoid of logic. Quite simply, time is better spent on questions with a basis in reality that can be investigated.
Actually a real answer to that queation based on evidence is hard to tell. You can find answers in different religions but you have to be believer " accept those answers without evidence". I think life on our earth as we know started with the emergence of the first living creature 4 billions years ago . That is the only thing attained to an evidence .
Before that time , no hard evidences for previous forms of life at least to my knowledge.
As regard to the definition of life itself , it's difficult to find a comprehensive definition . But you can describe the features of it entailing ability of metabolism and reproduction.when it comes to individuals I think the only thing that survived and was bigger than life is Genome. We are just carriers for that material in a specific period of time then we pass it to the next generation till the end of our species.