One of my buddies gave me about 150lbs of soybean seeds,he said to plant them for a food plot. Is it to late for this year?

Yes. They'd probably sprout, but there's not enough growing season left to let them develop. Save them til next year.

maybe plant 1/8 or 1/16 of an acre. it's too late to expect much, but this would make a good experiment. you'd find out how much they'd grow when planted at the end of august.