The training tutorial for Chow Chow to follow its owner when going out:
When training it to return, the most important thing is to make it realize that returning to its owner is a happy thing. For example, you can feed it some food after it comes back very obedient, or play with it with toys.
When training, you should start from a close distance first, and then gradually increase the training distance until finally it can return to you even if you let go of the leash.
Let it sit where it is and remain still
Holding the leash, let the Chow sit down and keep it there.
Slowly move away from it
After keeping it still, look at it while backing up, and slowly move away from it. The distance can be gradually increased starting from 1M.
While telling it "come here", trot back, so that the Chow Chow will follow its owner.
Give it a reward after returning
When the Chow Chow runs back to you, give it something to eat to encourage it. And gradually increase the length of the traction rope to increase the training distance.
The ideal result of return training is that it can return to its owner even if the leash is let go. After doing this, you can take it out for free.