TecMint published a tutorial about installing PostgreSQL and pgAdmin in Red Hat Enterprise Linux 8.
How to Install PostgreSQL and pgAdmin in RHEL 8
Pgadmin4 is an opensource web-based management tool for managing PostgreSQL databases. It’s a Python-based web-application developed using the flask framework at the backend and HTML5, CSS3, and Bootstrap on the frontend.
How to Install PostgreSQL and pgAdmin in RHEL 8