There are numerous quests in Merentha. The list of known quests can be seen in most class halls around the real with the list command. Nothing is needed to go on a quest. All you do is try to solve it. If the description of the quest talks of a man in Fenris a good starting place is to go to Fenris and find that man. Talking to monsters in the game sometimes helps.
Deeds are like mini-quests. There are literally hundreds of these within the game. There is no list of them and you are required to discover them and solve them yourself. All quest information is secret. The point of quests is to have fun while trying to solve the mystery. Telling others how to solve a quest is much like telling them how a movie they are watching ends. Giving quest information away (or selling it) it a violation of the rules. Please don't do so.
There are also some quests which are not listed. Quests to become different races or special classes are also considered quests. These are to remain secret as well and the solutions should not be told to anyone if you discover them.
There are no quest or deed requirements in Merentha. You can go though your entire Merentha life without ever having to do a quest, but if you do you lose out in a great part of what Merentha has to offer.