No, I can do both but absorb much better when I internal monologue it but can read much faster when I don't. Some people don't internal monologue it at all.

If you're in the market for another "wait I thought everyone did it X way?!" surprise look up aphantasia where some percentage of people can't mentally "picture" items and there's a whole spectrum of vividness. I've yet to find someone not surprised by this no matter where they are on the spectrum.

I have two modes of reading - when I read a story to enjoy, I read it to myself with inner voice saying the words (like internal audiobook). When I read to gather information quickly, I try to just absorb as much keywords as possible by quickly glancing at text and trying to directly absorb the text, rereading where needed.

No, and this is one of the first things that tends to come up in any guides on how to read more quickly: reading without internally vocalizing, in order to not limit reading to the speed of vocalizing.

Some people can switch back and forth between both readily, and use them for different purposes. Some people read only in one or the other mode.

Personally it's the same way you look at a thing and get a mental sense of "this is that thing" without having to scan every detail right away, you look at a chunk of a sentence or words and get the sense of its meaning, and you can vocalize that in your head if you want to

I have two reading modes: A narrative reading mode where a voice reads the text, and a speed reading mode where my eyes scan down the page and recognize the characters, words and phrases without any voice.

Not at all. I can do it, but I have to actively produce it. Don't see much use for it except when reading quality fiction. It's dog slow IME. You are a fast reader?

You might wonder how I read and it's a bit like how you can watch an intersection and know what to do without verbalizing "there is a bike", "there is a car". You just get the situation and understand it. Sentences are like that as well.

It is not.