Thank you for the biblical question, “What are the books of general letters in the New Testament?”
The three fold division of the New Testament are as follows:
A. The Gospels are Matthew, Mark, Luke, and John
B. The Historical book is Acts
C. The Epistles are divided into two divisions:
- The Pauline Epistles: Romans, I-II Corinthians, Galatians, Ephesians, Philippians, Colossians, I-II Timothy, Titus, and Philemon.
- The General Epistles: Hebrews, James, I-II Peter, I, II-III John, Jude, and Revelation.
The books place in the General Epistles are categorized as such because they are distinct from the Pauline epistles and are written by other apostles or church leaders.
SUMMARY: There are nine epistles in the General Epistles.
For more perspectives:
https://www.quora.com/What-are-the-books-of-general-letters-in-the-New-Testament