A Pokémon Booster Box contains 36 packs of Vivid Voltage Boosters pack.
Cards in each pack is completely random.
Here Pokémon's description for the new Vivid Voltage Set:
In Sword & Shield—Vivid Voltage, the recently discovered Mythical Pokémon Zarude makes its Pokémon TCG debut alongside other highly-collectible cards such as Pikachu VMAX, Orbeetle VMAX, and Coalossal VMAX shown in their Gigantamax forms.
The upcoming set will also debut a new type of card called Amazing Pokémon, which features a Legendary or Mythical Pokémon like Celebi, illustrated with vividly rainbow backgrounds that extend outside of the frame, as well as foil and etched details. Topped with a special rarity symbol, Trainers can look forward to collecting and playing with new Amazing Pokémon cards.
The full expansion includes the following: