The First or the Second epistle to Corinthians?

The thirteen epistles that are almost certainly written by Paul, in order, are:

Epistle to the Romans

First Epistle to the Corinthians

Second Epistle to the Corinthians

Epistle to the Galatians

Epistle to the Ephesians

Epistle to the Philippians

Epistle to the Colossians

First Epistle to the Thessalonians

Second Epistle to the Thessalonians

First Epistle to Timothy

Second Epistle to Timothy

Epistle to Titus

Epistle to Philemon

although some theologians doubt that some letters (eg Ephesians) are written by him as the style of writing is different from the others.

The fourteenth letter, the Epistle to the Hebrews - is unlikely to have been written by Paul. He doesn't claim to have written it nor is the style of writing his. Pauline authorship is rejected by modern scholarship and even in the early church its authorship was debated.

Epistles to the Thessalonians written from Corinth. Epistles to the Corinthians. Epistle to the Galations. Epistle to the Romans written from Corinth. Epistle to the Philippians. Epitle to the Colossians. Epistle to Philemon. Epistle to the Hebrews. Epistle to Titus.

The First Epistle to the Corinthians and the Second Epistle to the Corinthians were written by the apostle Paul.

The First Epistle of Peter and the Second Epistle of Peter are believed to have been written in Peter's name by anonymous authors, with the second book clearly a second-century work.

Mark's Gospel was originally anonymous, but was attributed to Mark early in the second century. This attribution is not accepted by modern scholars.

The Book of Hebrews has been attributed to Paul, but even the early Church Fathers realised that it was not an epistle he would have written. It remains anonymous.

The Book of Revelation is signed by a person called John. The early Church Fathers disputed who this 'John' really was, and finally decided to include it in case the author was the apostle John. Modern scholars refer to its author simply as 'John of Patmos'.