Yes, olive oil can be used instead of vegetable oil in most cases with a 1:1 substitution ratio. Olive oil is healthier and richer in nutrients since it is less processed than vegetable oil. It can enhance the flavor of your dish, especially in baking, salad dressings, marinades, and sautéing. However, olive oil has a more distinct taste, which might affect the final flavor of some recipes where neutral oil is desired. For deep frying, vegetable oil might be preferred if a neutral taste is important, but olive oil also works fine given its sufficiently high smoke point for home cooking.
