Is space hot or cold?

The bottom line: the temperature outer space is brutally cold. The gas particles may be moving really fast, having been energized by the sun, but the outer space is huge and gas particles and stars are lightyears away from one another. There will be no knocking into each other. There is simply too much space.

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Keeping this in consideration, is universe infinite or finite?

The observable universe is finite in that it hasn't existed forever. It extends 46 billion light years in every direction from us. (While our universe is 13.8 billion years old, the observable universe reaches further since the universe is expanding). Regarding this, how many universes are there? If we define "universe" as "all there is" or "all that exists," then obviously, by definition, there can be only one universe. But if we define "universe" as "all we can ever see" (no matter how large our telescopes) or "space-time regions that expand together," then many universes may indeed exist.

Then, how will the universe end?

Astronomers once thought the universe could collapse in a Big Crunch. Now most agree it will end with a Big Freeze. Trillions of years in the future, long after Earth is destroyed, the universe will drift apart until galaxy and star formation ceases. Slowly, stars will fizzle out, turning night skies black. One may also ask what came before the universe? The Universe has not existed forever. It was born. Around 13.82 billion years ago, matter, energy, space ? and time ? erupted into being in a fireball called the Big Bang. It expanded and, from the cooling debris, there congealed galaxies ? islands of stars of which our Milky Way is one among about two trillion.

And another question, can we create new matter?

To manufacture matter in a way that adheres to the first law of thermodynamics, you have to convert energy into matter. So yes, humans can manufacture matter. We can turn light into subatomic particles, but even the best scientists can't create something out of nothing.