While the speed of light remains a fundamental physical limit, there have been theoretical discussions about achieving relativistic speeds through concepts like the Alcubierre drive, but as of my last update, these ideas remain speculative and face significant challenges, including the need for exotic matter with negative energy density, which has not been observed or created.
Currently, space missions to Venus or any other planet within our solar system use conventional propulsion methods, such as chemical rockets or ion propulsion, which are far slower than the speed of light. The duration of the journey depends on the specific mission design and the relative positions of Earth and the target planet. For Venus missions, it typically takes several months to over a year to reach the planet.