The three ways that players can gain skill points are by leveling up, increasing the intelligence attribute, and reading skill books. However, if the player character has the highest party level Leader skills effect the party, but only the skill level of the party leader is taken into account. The level of the party skill is determined to be the highest level among the members of the party. Party skills (like Wound Treatment, Path-Finding, and Looting) effect how your party functions after battles and on the map. Personal skills (like ironflesh and tactics) effect the stats of an individual character. Skills can also be classified as either a personal, individual, or leader skill. For example, having 12 attribute points in Agility allows for a maximum of 4 points in skills like Weapon Master, Riding, and Athletics. Every three points that you have in an attribute increases the maximum number of points you can invest in a skill that is based on that attribute. Each of the 24 skills is classified into a category based on which of the 4 attributes (Strength, Agility, Intelligence, and Charisma) the skill is dependent on.
You can view your skills on the Character page. There are a variety of skills that the player can build up in the game.