To find the first word of power of Kyne’s Peace, Kyne, you will need to travel to Ragnvald. There is actually a puzel to open the way to the word of power, you have to find two skulls to be able to enter the chamber in which you can find the shout. You can find Ragnvald here:
On either side of the main chamber before the spikes that block the way above ground level you find doors. The door to the right, at ground level, goes to Ragnvald Temple. Here you will have to follow the path until you find the skull. When you take it a hefty mini boss will spawn along with a number of standard Draugr and other Draugr. I would focus down the weaker enemies and the kill the mini boss.
The left side goes to the Ragnvald Crypts. It can be found above and to the left of the main chamber. Follow the same tactic as described for the Ragnvald Temple.
At the end the boss is fairly tough. Do not rely on magic because Otar the Mad mainly does shock damage which takes away magicka. Do not bother trying to poison him because he usually resists the poison. You may have to lower the difficulty or make sure you break line of sight often and use a bow and arrow.
When you explore the chamber that you now have access to you will find the word of power Kyne of the shout Kyne’s Peace.