Planets have been around for a while it seems. Now, imagine an earth-like planet, with liquid water and enough carbon, nitrogen, iron, and oxygen to get the ball rolling, but life in this theoretical world has a 50 million year head start from our planet. 50 million years ago is not that long in the timeframe of a 14 Billion year old universe.
I love this idea, this line of questioning because it gets into chemistry, physics, deep time, philosophy, history, astronomy and always generates good discussions at events.
I believe that there is life out there. It may even be looking up in our direction. But I doubt that there will be any contact with 'aliens' in my lifetime. I do think we will 100% find confirmed living bacteria, and maybe basic multi-celular life in places like Enceladus and Europa in my lifetime.
Here is a curve ball for you, just something to think about. I hope that life looks exactly like life on earth. If we find living things out there in the solar system and it looks different than earth life? Then the concept of a Great filter gets really fucking terrifying. If life pops up on 3-4 places in a solar system, and we have no evidence of sentient life out there in space, maybe there is a filter we are approaching that no other living thing was able to break through. IF, however, all that life is the same amino acids and DNA as earth life, that starts to look like life started once in the solar system then spread through asteroid and comet impacts. We know life can survive in space and we know that rocks from the earth and Mars and the Asteroid Belt interact with each other over time. Either thought is both amazing and terrifying to contemplate.