You can do up to 50 quests at a time. Track your quest progress by typing /quests started.
There are 7 main categories that you'll be looking at in the quests menu.
Rank Quests
Amount: 27 Rank quests, 88 Prestige rank quests, 115 total
Reward type: Varying with each rank
Here you will find the quests that are available to you in regards to your rank and progress. These will change dynamically each time you rank up, so you will only ever see the quests you need to complete to get to the next rank.
Mining Quests
Amount: 50 total quests
Reward type: Money
This category contains quests pertaining to mining and breaking blocks.
All mining quests are 1-time only. Once you complete one, you will not be able to repeat it or even view it in the menu anymore.
Combat Quests
Amount: 49
Reward type: Money
This category contains quests pertaining to killing mobs.
All combat quests are 1-time only. Once you complete one, you will not be able to repeat it or even view it in the menu anymore.
Farming/Food Quests
Amount: 35
Reward type: Money
This category contains quests pertaining to farming, gathering, and making food.
All farming/food quests are 1-time only. Once you complete one, you will not be able to repeat it or even view it in the menu anymore.
Husbandry Quests
Amount: 8
Reward type: Money
This category contains quests pertaining to taking care of animals.
All husbandry quests are 1-time only. Once you complete one, you will not be able to repeat it or even view it in the menu anymore.
Miscellaneous Quests
Amount: 6
Reward type: Money
This category contains quests pertaining to enchanting, brewing, and fishing.
All miscellaneous quests are 1-time only. Once you complete one, you will not be able to repeat it or even view it in the menu anymore.
Repeatable Quests (daily quests)
Amount: 67
Reward type: Money and Tokens
This category contains quests of all types, coming from all other categories. They are much easier to achieve.
Dungeon Quests
When you teleport to a dungeon, a quest will automatically start for you. This quest will complete when you finish the dungeon.
Forgotten Mine has an extra 'quest' within the dungeon. You'll know it when you find it, and this quest is for you to obtain a key item needed for you to finish.