In American English it's 'for un.' Not for reign [ rain ] as Beni states. Maybe you didn't see it but Elizabeth gave you the correct answer here: https://www.italki.com/discussion/82672

This word is pronounced as such: Fo= the "o" that is in "story" Reign= this syllable is like "run" with a "shwa", which sounds like "ren" instead of "ran" You don't say "forend" as you mentioned. The end of the word is un unstressed syllable, that's why we use a "shwa", which is the "e" sound as in "the". Note that this is the British pronunciation; the American one use a longer "o" sound for "fo", as in the preposition "for". "Reign" is the same in American as well. Does that make sense?

You are correct, the second syllable is like 'end' without the 'd'. The emphasis is on the first syllable, the 'for'.