No, NASA has not landed any spacecraft on Neptune or Venus to date.
Venus has been explored by various space missions, including several missions by NASA. These missions include the Mariner program (Mariner 2, Mariner 5, and Mariner 10) in the 1960s and 1970s, the Pioneer Venus program (Pioneer Venus Orbiter and Pioneer Venus Multiprobe) in the late 1970s, and more recently, the Magellan mission (1990-1994) that mapped the surface of Venus using radar. However, none of these missions involved landing on the surface of Venus. Due to the extreme conditions on Venus, including a thick atmosphere, high temperatures, and pressure, landing and operating a spacecraft on its surface presents significant technical challenges.
As for Neptune, NASA has not sent any dedicated missions to explore the planet directly. The Voyager 2 spacecraft, launched in 1977, conducted a flyby of Neptune in 1989, providing valuable data and close-up images of the planet and its moons. However, Voyager 2 did not land on Neptune but rather performed a close flyby, capturing data as it passed by the planet and its moon Triton.
It's worth noting that space exploration is an ongoing endeavor, and future missions may be planned to further explore and study Venus, Neptune, and other celestial bodies in our solar system.