Are linemen eligible to receive the ball, by pass or lateral, behind the line of scrimmage and attempt a forward pass the way flankers and wide-outs are?

yes

YEA, IF U ARE ONE OF THOSE UNATHLETIC TEAMS THAT NEEDS TO RELY ON THINGS LIKE THAT

double passing is the bomb. dont hate because your team is not athletic enough to play like that

es right Don`t hate