If you control no creature tokens when you populate, nothing will happen.

If you choose to copy a creature token that's a copy of another creature, the new creature token will copy the characteristics of whatever the original token is copying.

The new creature token copies the characteristics of the original token as stated by the effect that created the original token.

The new token doesn't copy whether the original token is tapped or untapped, whether it has any counters on it or Auras and Equipment attached to it, or any noncopy effects that have changed its power, toughness, color, and so on.

Any enters-the-battlefield abilities of the copied token will trigger when the new token enters the battlefield. Any "as [this creature] enters the battlefield" or "[this creature] enters the battlefield with" abilities of the copied token will also work.

Populate doesn't target the creature token you're copying. You choose that creature token as you're taking the populate action. You can choose any creature token you control. If a spell or ability causes you to create a creature token and then instructs you to populate, you may choose to copy the token you just created, or you may choose to copy another creature token you control.

Although the token is an attacking creature, it was never declared as an attacking creature. This means that abilities that trigger whenever a creature attacks won't trigger when it enters the battlefield attacking.

Any effects that say that the token can't attack (such as that of Doomed Artisan, or if you copy a token with defender) affect only the declaration of attackers. They won't stop the token you populate from entering the battlefield attacking.

In some rare cases, you might copy a creature token that isn't normally a creature. This token enters the battlefield as a noncreature permanent. It will be tapped but it won't be attacking.

You choose which player or planeswalker the created token is attacking. It doesn't have to be attacking the same player or planeswalker that Ghired is attacking.