You do not need to configure Apache to work with JBoss AS - JBoss AS has a built in web server that can server HTML and other pages. Since you are a beginner, it would be easier if you started simple. Once you are comfortable working with apps running in JBoss AS, then you can start to consider setting up an Apache front end.
If you still want to set up Apache with JBoss AS, this might help:
https://community.jboss.org/wiki/UsingModjk12WithJBoss
Of if you want to use mod_proxy, see this:
http://httpd.apache.org/docs/2.0/mod/mod_proxy.html