It is Jan and you will fly to Japan in March. In American English, you say: "I will fly to Japan 2 months from now". Can you instead say "I will fly to Japan 2 months later"?
Is there any other alternative for "from now" in this case?
"2 months later" implies that you have mentioned a date already and are referring to a point two months after that date, e.g. I'll be checking out some hotels next week, and I will fly to Japan 2 months later.
As for an alternative, you may replace "from now" in the sentence by prepending the word "in" to the time measurement: I will fly to japan in two months.