Which of the following is not true about theme?

a theme may be explicit or implicit.

there can be more than one theme in a narrative.

a theme is found in the beginning of the story.

a character does not always learn the life lesson.

The answer which is not true about theme is that a theme is found in the beginning of the story.
It is unlikely that the theme will be presented in the very beginning of the story, as it usually develops throughout the text. The other options are indeed correct.