I wanted to share latest update&details for current database support&end of life.
Short information can be found below. For more details you can check this link

The bug fixing has been ended for Oracle on Nov 20, 2020. For is running on the limited Error Correction from Dec 1, 2020 through March 31, 2022. (PS: Limited Error Correction means you can open Sev 1 Sr and follow Security Updates only)

You need to 19c version which that gives you a long term support, as the full span of bug fixing support until 31-APR-2024. THis version have Extended Support until 31-Apr-2027. Premier Support (PS) ends April 30, 2024 and you need to pay Extended Support (ES) fees beginning May 01, 2024 through April 30, 2027.

For fully details available at
Release Schedule of Current Database Releases (Doc ID 742060.1)