The way to gain quests and part of its nature

You gain quests by communicating with non-player characters. The specific steps you should take to get quests are firstly walking up to an NPC, and then press F while targeting him. After doing this, you can see a dialogue window, you can purchase and sell items, train skills and spells, or get quests depending on what services this NPC offers. When you finish quests for NPCs, new quests may unlock. Some quests among those are with the repeatable nature, which means they can be done as many times as you like. Those quests are usually kill-quests with random rewards.