I do believe in Alien Civilization, they might exist in many parts of the universe. The Universe is just way too massive and not even a speed of light could bring you to another Galaxy unless we could find way to unlock immortality and infinite energy. Hence in Alien life perspective there are low chances imo for them to meet us, Because we are limited in only our Galaxy. 100,000,000 habitable planet could not be enough. Chances are these planets rarely creates a intelligent species like us, maybe some of them exist but wiped out because of any catastrophic events. Maybe we could meet them one day.