"Head-on" means "directly". When you deal with a problem "head-on", it means that you do it energetically, and without hesitation.

Here are the common actions that people do "head-on":

face (something) head-on

challenge (someone) head-on

tackle a problem head-on

address (somethiing) head-on

confront (someone) head-on

Doing things "head-on" is almost always positive. Most people agree that problems should be handled "head-on".