Apex Packs/Coins
Apex Packs have three various cosmetics in each pack. According to Respawn.
You can also buy Apex Packs through Apex Legends' premium currencys, Apex Coins.

- 1 Apex Pack costs 100 Apex Coins (~$1.00 USD)
- 10 Apex Packs cost 1,000 Apex Coins ($9.99 USD)
Apex Packs Chances and Loot
Apex Packs do not drop duplicates. Here are the probabilities of drops having something greater than common items:
- 100% - Rare Item or Better
- 24.8% - Epic or Better
- 7.4% - Legendary
Apex Packs also have a thing called "bad luck protection," which means at least one Legendary item withing 30 pulls.
Cosmetic types:
- Weapon Skins
- Legend Skins
- Legend Finishers
- Banner Frames
- Banner Poses
- Banner Stat Trackers
- Intro Quips
- Kill Quips
- Crafting Metals
Bonus Heirloom Set
The Bonus Heirloom set is a very, very special drop with a <1% chance it'll drop. There is currently only one Heirloom Set in Apex Legends. This set has three items for Wraith -- a Banner Pose, a Melee Weapon Skin, and an Intro Quip.
Here's an image of the Heirloom Set.

Apex Legends Currency.
Apex Legends features three kinds of currency. Legend Tokens and Crafting Metals can only be earned by playing Apex Legends, but Apex Coins are available for purchase.
- Apex Coins - Apex Legends' premium currency that can be purchased with real money and earned by playing. You can spend it in the rotating shop.
- Legend Tokens - These can only be earned by playing Apex Legends. You can use them to unlock Legends and select cosmetics.
- Crafting Metals - These are only earned through Apex Packs. Use them to craft most cosmetics.