If multiple creatures go to the graveyard at once, Angelic Renewal triggers multiple times, but it can only be sacrificed once and only brings back one creature.

If this card goes to the graveyard at the same time as a creature or sometime between when the creature left the battlefield and when the triggered ability resolves, then you will not be able to sacrifice this card and the creature can’t be returned to the battlefield.

If an animated permanent that’s not normally a creature is put into your graveyard from the battlefield, Angelic Renewal can return that card to the battlefield.

If a token creature is put into your graveyard from the battlefield, you can sacrifice Angelic Renewal, but nothing will be returned to the battlefield.