In a large saucepan of 3 cups water, cook rice according to package instructions; set aside.
Set a 6-qt Instant Pot to the high sauté setting. Add olive oil and sausage. Cook, stirring frequently, until sausage is lightly browned, about 3-4 minutes. Transfer to a paper towel-lined plate; set aside.
Add garlic, onion, bell pepper and celery. Cook, stirring occasionally, until tender, about 2-3 minutes.
Stir in sausage, red beans, Cajun seasoning, oregano, basil, sage, thyme, bay leaves and vegetable broth; season with salt and pepper, to taste.
Select manual setting; adjust pressure to high, and set time for 40-45 minutes. When finished cooking, release pressure naturally according to manufacturer's directions, about 20-30 minutes.
Serve immediately with rice and hot sauce, garnished with green onions, if desired.