I need a little help.

I'm trying to train my dog with a "look" command. Basically, I want to say the command, and then he'll look at me no matter what.

It's going great at home. He listens every time. But i'm having trouble getting him to respond while on walks. I want to eventually get to off-leashing, and i know that teaching this command can be super helpful in getting to that point, but he doesn't really listen to ANY command while on walks. It's like he just zones out and doesn't realize i'm talking. I have to stop and let him run the leash out for him to even realize i'm there.