Hi Vinny,
Armageddon is a battle in a war on planet earth, nothing more Revelation 9:16. It is only mentioned specifically once by name in the bible Revelation 16:16, although it is referred to on a few other occasions. What makes it a bit significant is that marks the start of Christ's Millennial reign. Thereafter, the day of judgement is at the "end of the age" Matthew 13:38-40 which leads to everlasting life for some and the second death (everlasting torment) for others.
So are you asking will Christians die in the battle? Yes.
There will be "tribulation saints", those that miss the rapture Matthew 24:40-42 but don't take the mark or worship the beast Revelation 7:15
The important thing to note is that everyone who dies will get resurrected, some to everlasting life and others everlasting shame Daniel 12:2
Read Revelation 20 Revelation 21 They are pretty easy to follow and have it all in a nutshell.
All the best,
Stephen