I am new toi linux too, and I just went through some of this. Drove me nuts.
For postgres yo uneed to create a new user pretty much expressly for the use of starting postgres.
adduser postgres
passwd postgres
That will get you your user. The default data directory for postgres if you installed to /usr/local/pgsql will be /usr/local/pgsql/data so we need to setup the new postgres user for that
chown /usr/local/pgsql/data postgres
Finally go into the bin dir and start postgres
su postgres
(enter password for user postgres)
cd /usr/local/pgsql/bin
./postmaster -D /usr/local/pgsql/data &
That will take care of that.
As for Apache, find the httpd file
find / -name httpd
It is probably located in /usr/local/apache. If it is
cd /usr/local/apache/bin
./apachectl start
would be best to get it up and running.
Any mistakes, I apologize in advance. I am new, trying to help, and going off of memory, heh.
HTH!