We can travel to the past and future then we can know the future at present moment (traveled in the future , knew everything and back again to the past). Then how can we say that we have free will? We have to perform the event which we seen from the future?
Not exactly. We can only 'time travel' into the future. We can't go back in time. According to einstein's theory of space-time relativity, space and time are related. So, the faster you move through space, the faster you move through time. So if your speed increases, the way 'time' passes around you seems faster. But to people looking at you, they see you just going slower, if that makes sense.
So to travel into the future, you'd need to go at a positive speed. But to go backwards, you'd need to go at a negative speed, and that isn't possible.
Suppose you had a machine that would get you going very, very fast, and person A was inside it. Person B is outside of it. Person A is watching a timer outside the machine, and it seems twice as fast. Person B, however, is watching a timer inside the machine, and it seems twice as slow.
If you wanted to jump forward five years, then at a very, very fast speed it would only seem like one year to you. To you, you go in the machine for a year, come out, and it's 2025. But to everyone else, you just go inside a machine and come out five years later.
So the answer is no, you would not be able to deny free will, because time traveling forward is just an illusion.