More than 50 years of searching for signals from other civilizations in the Universe has produced a deafening silence. There is no evidence that aliens have visited the Earth or exist anywhere. There are many hints that life might exist in other places but there is no conclusive proof that it does.
My money is on the concept that there are many planets which host living organisms. Recent discoveries indicate that there may be as many as 40 billion habitable planets in the Milky way alone. On some of them civilizations like are ours are likely to be emerging. The physics of the Universe requires large allocations of energy and resources to become spacefaring. Humans have so far dabbled in a few baby steps beyond our planet and made some attempts to listen for other beings. What else is out there remains to be discovered.