Once you have reached 100 in all major and minor skills, you are at your character's maximum level, which varies depending on a few different factors. Major skills start out at 30 and minor skills start out at 15, which means you potentially have 775 skill increases that count towards level. However, most characters have additional bonuses to these skills at character creation, from specialty or race or birthsign. This makes those skills easier to use from the beginning, but limits the maximum level that the character can attain, which also limits the maximum amount of base health.