Pork Roast in the Instant Pot

1 pork roast 2 cups water OR chicken broth ( I used 1 cup of each) 1 & ½ tsp salt 1 & ½ tsp pepper 1 tsp onion powder 2 tbsp. olive oil (divided) 1 small onion, sliced into quarters About 3 garlic cloves –sliced or minced