Can we travel into future if we invent a time machine

also what is grandfather paradox?
Can we change the past?

Im pretty sure a time machine is impossible but the Grandfather paradox is if you were to meet your grandmother in the past on the day that she met your grandad. You convince her to go somewhere else, say a concert or game and she never mees your grandad. Although this is where the paradox comes in because if your grandparents never met, never had your parents. How could you have existed to build a time machine?
There is a thing called the Arrow of time which means that time travels forwards and, like an arrow, dosent stop or go the opposite direction. Hope I helped and didnt kill any dreams. :D

No and no.

Even if we somehow achieve faster than light travel, we will also need to move through space, so there will be no plug-and-play travel into future, while staying in the same place.

Grandfather paradox is a paradox about what would happen if you go into past and kill your grandfather. How can you even exist than, if you killed your grandpa before he made your father and so on...

Yes, Time Travel to your future is easy.

Time Travel into the future is possible. If Free Will exists, then time travel into the past is not possible, IF there is only one universe. But, some versions of Quantum Mechanics proposes multiple universes. Multiple universes are possible, then time travel to the past is also possible. Though any change made in the past results in living on a different time line. (Example of the fun you can have with this: Solution to the “Grandfather Paradox,” If you go back in time it is impossible to kill your grandfather. Every time you try the gun mis-fires and you stay on a time line where your grandfather lives. See:
http://en.wikipedia.org/wiki/Grandfather…
http://science.howstuffworks.com/science…

Two Time Machines for travel into the future: