"Listening" is happening right now. "Listened" happened in the past.
I am sitting in my chair. I am looking at the TV. I am listening to a news program. These are examples of the present progressive tense. They all use verb forms ending in -ing.
"Listened" happened in the past. An hour ago, a day ago, a century ago.
Yesterday I listened to the news on TV.
When I was a little kid, I listened to what my mother said.
In 1863, a crowd listened silently while Prsident Abraham Lincoln gave a speech.