Confession is one element of the commandment of repentance. The daily morning and afternoon prayers on weekdays include a general confession ("Ashamnu" - "we are guilty"), recited by each worshipper in a whisper. On Yom Kippur, a confession composed specifically for this day ("Al Chet" - "for sin") is recited multiple times.
The "Ashamnu" prayer contains 22 expressions of guilt, sinfulness, misdeeds, etc., in alphabetical order. The first person plural ("we are guilty") is used here to emphasize the mutual responsibility we must feel for each misdeed. Consequently, this prayer can be recited even by a righteous person who has never actually committed any of the serious sins listed in the "Ashamnu" prayer. Of course, each person is personally responsible for their actions, but it is also true that the Jewish people as a whole are like a single organism, in which the shortcomings of one organ inevitably affect the entire organism. Therefore, when a Jew sins, it correspondingly affects the entire Jewish people, and when a Jew does a good deed, the entire Jewish people benefits.