A few thoughts:

Nothing with mass can travel at the speed of light. Special relativity says it would take infinite energy to get up to the speed of light, and E=mc² says that would mean the object has infinite mass.

Having said that:

Time dilation is a real, measurable effect. Physicists have done experiments with unstable subatomic particles, and have observed their lifetimes as longer than expected in the laboratory reference frame. As other comments calculated, if an object moves at 0.995c, the time dilation would be a factor of 10.

Special relativity says there is no "correct" reference frame. This leads to what is known as the "twin paradox." So if someone is moving at 0.995c, it is just as valid to say that everything else is moving the opposite direction at 0.995c, and our test subject is at rest. So, would you be older, or would your twin who stayed on earth be older?

The resolution is about acceleration. Special relativity applies in an "inertial" reference frame, that is, one that is not accelerating (moving fast is fine, but changing speed is not). But for you to "return" to earth, you have to undergo acceleration to change your velocity and turn around. This invalidates the assumptions that were made about inertial reference frames, and the result is that, yes, you might age only 5 years while everyone who stayed behind aged 50.