More on the "As you know, Admiral," mistake

The “As you know, Admiral,” syndrome is quite common in
technothrillers. Heck, I’ve done it myself on numerous occasions. You
know what I’m talking about—it’s when the hotshot pilot who’s about to
take off on a suicide mission says something like, “As you know,
Admiral, the Phoenix missile has a maximum range of one hundred
nautical miles and flies at a speed of Mach 4.”

Now, don’t email me to complain that that’s not accurate. I don’t care. I
don’t write missiles very often any more.

The point is that there’s a character telling another character stuff that
they both already know. Come on, the guy’s an ADMIRAL. You think
he got those stars without knowing what a Phoenix can do? No – he
didn’t, and you’ve violated a bunch of principles of good storytelling,
including the ones about creating human characters.

Now, there ARE times when you’ll need to fill your reader in on
technical details of some sort or another. That’s fine, with two caveats:
do it in narrative, not dialogue, and don’t do it in the first paragraphs.
Because that’s what we’re talking about here, right? The first few pages.

One other small point about first paragraphs and worlds – many new
writers lack confidence that they’ve actually created the world. They’ll do
something, then do it again in another way just to make sure they’ve
made their points.

You’ll get over this with time. The immediate cure is to have an
experienced writer look over your work.