If you are looking to work with Apache on OSX you have probably been advised to not use the Apache 2.4 pre-installed version because Apple has removed some required scripts, especially in the macOS 10.15 Catalina release.
Here are the commands to run to install Apache via brew.
First shutdown Apache and unload any scripts.
$ sudo apachectl stop
$ sudo launchctl unload -w /System/Library/LaunchDaemons/org.apache.httpd.plist 2>/dev/null
The install httpd with brew.
brew install httpd
Then start Apache again with:
sudo apachectl start
To watch the log files:
tail -f /usr/local/var/log/httpd/error_log
Now here is the interesting part. You need to know where to find the httpd.conf file because this file determines various key settings such as port number and ip address among other things.
usr/local/etc/httpd/httpd.conf //brew private/etc/apache2/httpd.conf //osx default
web server root dir
usr/local/var/www //brew Library/WebServer/Documents //osx default