postgres initial startup

[Jean Fleurant (root)]

I'd like to use postgres database to run a buletin board called phpBB2.

I'm pretty new in linux and I've spent almost 2 days trying to start the postgrea database.

In the documentation that come in the installation, it is always specified to run "postmaster -D database_path" but I don't know what is the database path.

Where should I start and is there documentation applicable to the version that come with RedHat 8.

Please help me.