“I'm seeing a movie on Saturday.”
I'm seeing … uses the present continuous for a near-future arrangement, as in A1-14. The speaker plans to see a movie on Saturday. In American English, movie is more usual than film in this expression.
A1-23 / CEFR A1 / EPISODE 23
Talking about weekend plans
SceneIn class, discussing weekend plans.

WORDS & CONTEXT
I'm seeing … uses the present continuous for a near-future arrangement, as in A1-14. The speaker plans to see a movie on Saturday. In American English, movie is more usual than film in this expression.
Here way is an informal American intensifier meaning “much” or “far,” rather than a road. Way more fun than … means much more enjoyable than something else.