Of course there are other planets capable of sustaining life. To think this planet was created by god or something outlandish is just crazy. I have a feeling others are far more developed, and will find us first. We've been to busy spending our resources on war and other useless things.
It was once thought that we could go to mars in the next 10-20 years but like I said with all the war and hatred, it's not gonna get done IMO.
As sad as it is, war/fighting is quite a natural thing. Eaten or be eaten. Every species on this planet has evolved some kind of "weapon" to kill or to survive, be it fangs, claws, poison, strength, speed etc. And actually the cold war was what led to most advancements in the space programs of the US and former USSR.
As for extraterrestrial life, since the late 1980s early 1990s scientists find more and more planetsystems in space. So far they've found close to 800 planets. It's still difficult to prove Earth-like planets as our instruments are not sensible enough yet. But it's highly probable that there are a lot of Earth-like planets that could support life.
Contact with extraterrestrial lifeforms is a problem though. We can only communicate with the speed of light (so far). Most planetary systems found so far are more than a 100 light years away, so any message send would take more than a generation to arrive. To travel these distances we would need generation space ships, but by now we still struggle to make a safe travel to our moon which is a mere light second
away. So unless we don't find a trick to deny our understanding of phyics, there won't be any kind of travel similar to what we do now on Earth between countries and continents.