“I won’t be able to use much the computer today. I have to go to a place.”
“It’s incredible how flies the time! It will be Christmas soon!”
Sorry, I am still learning English. I hear many people who have second-language English that is my friends say that though.
Close…
“I won’t be able to use much the computer today. I have to go to a place.”
Should be:
“I won’t be able to use the computer much today, I have to go to a place.”
Alternately:
“I won’t be able to use the computer very much today, I have to go to a place.”
Much (or very much) is modifying the action of using the computer, so it comes after.
“It’s incredible how flies the time! It will be Christmas soon!”
Same issue here…
“It’s incredible how time flies! It will be Christmas soon!”
The idiom is “time flies”, flies, the modifier, comes after. “The” isn’t needed and can be left out.
English has a LOT of weird rules, but there are good books that explain EVERYTHING:
Strunk and White’s “Elements of Style” is kind of the gold standard and it’s old enough now that it’s public domain:
https://www.gutenberg.org/ebooks/37134
While not free, I’d also suggest the Borzoi Handbook for Writers:
https://www.amazon.com/dp/0394332016