Developing space technology is also beneficial for the same reason you want the first and best of any technology -- if you don't, somebody else will (e.g. China, Russia).
Just off the top of my head.
> Second reason is why?
Isn't that the same as the first question? I won't say that NASA is a shining example of project management or even the best way to go about conducting space science. Government-funded (i.e. taxpayer-funded) science has inherent economic problems that make even attaching a real value to it near impossible. However, to make claims like they're "spending billions of dollars" just to put "metal in space" is colossally ignorant.
> First off, Humans have been on Earth for many years. I doubt that we are really that close to running out of resources.
For most of that history, we weren't burning through 85,294,571 barrels of oil per day. Fossil fuels are a delicately finite resource. It's not just about running out, but of running out of the easy-to-get-to fuels that make purchasing them affordable. We also have to consider what is happening to our environment as a result of the current energy paradigm.
> Second, why do humans get a second chance?
Because we are sapient creatures with the ability to create second chances for ourselves.
> If humans (me included) screw up this world that its we must rely on another planet then we don't even deserve this one. We will die by natural selection.
Naturalistic fallacy. Just because something might naturally entail one consequence or another, that isn't a valid argument for why it ought to be one way as opposed to some other way.