The closest star to our Sun is Proxima Centauri, it is one of three stars that are all orbiting a common center of gravity. Proxima Centauri is a Red dwarf star and is very small and dim compared to the sun. We know it has some rocky Earth like planets going around it but we don't know very much else. The two other stars are Alpha Centauri A, a sun like Yellow dwarf star and Alpa Centauri B, a smaller Orange dwarf star that is half as bright as the Sun. If you look the Alpha Centauri stars without a telescope, they look like one star.
Even though they are the closest stars to us, the distance between them and us is immense. It takes light 4.2 years to go from the sun to Proxima Centauri. It takes less than a day for light to go from the sun to the voyager 1 probe, the most distant man made object in space (16 hours). The nearest stars to our sun are more than 5,000 times further away than our most distant probe that has been speeding away from the Earth for decades. It is hard to even imagine that distance, and they are just the nearest stars.