Here's a first try at building a star system using The Planet Builder, ended up with single star system with 6 planets, and an asteroid belt, 1 planet has 3 moons, 1 planet has 1 moon, another has 2 moons, and a final colossal planet has 5 moons, but 2 have collided with another closing in. And it's 3 pages of stat block - so just showing an excerpt of the whole stat block.
Stygian star system Tier 9
Single Star, orange dwarf type K, 2.5 billion years,
6 planets and belt, Erebus (Stygian Prime), 240 PP (14 PP)
Araphel (Stygian II) planetoid, .01 Earth masses, rocky,
microgravity, 80% metallic, hot zone
Atmosphere none
Hydrosphere none
Lifeforms none
Intelligent Life none
Trade Resources neodymium deposit
Megastructures orbital ore processor
Moons none
Apep (Stygian III) huge planet, 18 Earth masses, gaseous,
high gravity, hot zone
Atmosphere gaseous
Hydrosphere none
Lifeforms none
Intelligent Life none
Trade Resources deuterium in upper middle layer
Megastructures gas/liquid harvester processor,
atmospheric wind generator
Moons 3
Mehen (Moon I) small planet, .08 Earth masses, rocky,
low gravity, icy/rocky core
Atmosphere thin toxic, infrequent breezes
Hydrosphere large frozen seas, infrequent light rains
Lifeforms rare complex life
Intelligent Life none
Trade Resources Tungsten, Silver
Megastructures none
Unut (Moon II) planetoid, .0025 Earth masses, rocky,
microgravity, rocky core
Atmosphere none
Hydrosphere none
Lifeforms microscopic simple life
Intelligent Life none
Trade Resources none
Megastructures none
Wadjet (Moon III) small planetoid, .0000006 Earth masses,
rocky, microgravity, rocky core
Atmosphere none
Hydrosphere none
Lifeforms none
Intelligent Life none
Trade Resources none
Megastructures none