Compared to the devastation of past plagues and famines, life is pretty good these days.
We do need to be concerned about the existential threats of nuclear or biological warfare, or the remote but possible meteor strike that will wipe out the earth as we know it.
But stuff like microplastics, global warming, overpopulation, underpopulation, etc. etc. etc. though they are real issues that we need to address or adapt to, they are not something to fear.
Humans are the most adaptive creatures in the history of our world. And we will become even more adaptive with time.
We will continue to explore space and there may be a time to move to Mars or perhaps simply mine some materials there. But likely not in our lifetime.
Not only will we adapt, but humans will continue to evolve and who knows what we will evolve to, though some of the theories are pretty interesting. Like the idea that humans will be supplanted by machines which will inherit many of our traits, though not our biology.
Fun to ponder, but foolish to worry about.