Paul writes 3 letters to to the Bishops of the congregations in the area.
Timothy is the Bishop of Ephesus. He is young and while Ephesus is a great congregation, there are challenges. Paul gives Timothy advice (Tim is Paul's protege) about doctrine and practical application.
Titus is the Bishop in Crete. The Cretan church has its own challenges.
Paul writes to advise on both
1. Doctrine of Christ
2. Practical Application
These are awesome letters. How to shepherd your ward, help in your calling. I love these letters and you will, too.