Folah,
You seem to have a serious issue with the difference between singular and plural. Gen 5 speaks of "the generations" of Adam (aka "man", as verse 2 points out - He called them Adam).
Besides that, the Hebrew word that is rendered "generations" here, isn't even the plural of the word that normally refers to a generation, but a special expression for a genealogy or pedigree. So you're actually referring to oranges to prove that apples are citrus fruits.