Tasks are quests that you can complete and get the rewards daily. Tasks are technically part of players’ daily routine since the rewards and tasks are refreshed daily along with the Daily Reset. There are 16 Daily Tasks but you only need to do at least 9 of them to get the bonus rewards, as listed below:
On the other hand, Achievements are long-term Tasks where you can only obtain the rewards once. The rewards are shared by the same Family since they are given to the family as a whole. More achievements might be added as the game gets more content.