To begin is the hardest thing of all, isn’t it?
Here is a little trick the might get you going.
Think about your first pages as throwaways. Warmup. Clearing your throat.
Decide that once you really get going, after you’ve got some solid pages down, you’ll go back and chop off those first pages. One, maybe two, maybe three or more.
You’ll know exactly where to chop, too. You’ll feel it. The story will really start picking up steam, and that’s exactly where you cut off all that warmup.
Easy peasy.