Stars can vary greatly in size, and some can indeed be significantly larger than our Sun. The size of a star is typically measured in terms of its radius or diameter, and the largest known stars can have radii hundreds or even thousands of times greater than that of the Sun. To give you a sense of scale, the Sun has a radius of about 696,340 kilometers (432,450 miles).
The largest known star, called UY Scuti, is a red supergiant located in the constellation Scutum. It has an estimated radius of around 1,700 times that of the Sun, making it one of the largest stars known to astronomers. If we were to place UY Scuti in our solar system, its outer layers would extend beyond the orbit of Jupiter.
Regarding the possibility of stars having multiple planets like our solar system, it is indeed plausible. In fact, numerous exoplanetary systems have been discovered with planets orbiting a single star. These systems can have various configurations, including planets of different sizes and distances from their host star. Some exoplanet systems even have multiple planets within the habitable zone, where conditions could potentially support life as we know it.
Therefore, it is conceivable that there could be stars larger than our Sun around which multiple planets exist, forming their own planetary systems. The exact formation and arrangement of planets around stars depend on various factors such as the star's mass, composition, and the dynamics of the protoplanetary disk during the star's formation.