I was taught to use a 7 to 9 iron for chipping. Putting grip, putting stance, putting swing. Get the ball on the green and rolling as soon as possible.
Difference in club is how much fairway/fringe versus green.
Little fairway/fringe, lot of green, say 20/80 then 7 iron
half and half, 8 iron
Lot of fairway/fringe, say 70/30, then 9 iron