Confusion about combat and initiative

[Dead_DDP]

Reading through the Combat chapter of the 2023 version of BRP confuses me a lot, so I'm just gonna kinda go through step by step and explain what I don't get. Hopefully it'll be understandable.

STATEMENTS: So this is just players saying what they're going to be doing in a given round, right? Why would players feel the need to delay stating what they're going to be doing later in the turn then? Does delaying your Statement affect your action initiative in the Action phase? Also, if two players or a player and an NPC have the same DEX rank, why would they need to roll skill checks to determine who says what they want to do first? And if what a player states they're planning to do becomes impossible or they want to change, are they just screwed out of a turn?

POWERS: This is mostly confusion surrounding how powers work, but it ties into combat. So if the power you're using doesn't say "Instantaneous" in the Duration, it doesn't activate this turn but next. For example, say I'm playing a Magic user and I'm casting Blast. Because it's instantaneous, on the turn I say I'm casting it I resolve it. I spend the 3 power points and it deals 1d6 damage to a target. But if I was casting Change instead, I announce that I'm casting and then on my INT rank the following round, it activates and I spend the 1 power point then, right? And I can't move until after they've activated power, because the Action phase isn't until after the Powers phase.

ACTION: With movement affecting your DEX rank in initiative, do the penalties apply before they've even moved? Like, if my character wanted to move and then do something, would I move and then how far I moved affect when I can do the thing I'm trying? Or would I have to declare in the Statements phase that I planned on moving, say, 15 meters and then my DEX rank in the Action phase is halved right from the start.

RESOLUTION: Is this actually a phase? From reading the other phases it sounds like things are resolved during the Powers and Action phases as things are rolled. Don't understand why Resolution is listed as a separate phase.