Alien army

Humans have discovered intergalactic travel, and I’ve discovered that life is on almost every planet one of the most powerful alien races want to take earth for themselves, but they don’t have guns. They only have metal armor and sword also aliens are surprised that humans have came up with computers and basically other technology before space travel, and they don’t know about guns or nukes. Anyway the strongest race shows up with their commander.Jubule and their army stands in the battlefield waiting for the humans to come out what will you do?