Can’t stop topping/thinning my long irons - anything above a 7i

I’ve watched so many videos about how to swing my long irons and I just can’t arrive at any sort of consistency. I know I need to get my club head to follow my grip to hit it square. I know it needs to be more forward in my stance. I’m doing my best to get my hips to fire first. Was there anything that changed how you hit your long irons for you? How can I start to pure these things?