Rookie looking for a bike

[Beginner]

I want to buy an outdoor bike for exercise. Haven't ridden one in years. I am age 73, in good health. I will be cycling on city streets, walking paths and packed dirt roads. I need a step through/low entry bike. I've been looking at the following types: comfort, cruiser, hybrid. $500 to $1000. Could you please offer some advice on type of bike, brands and models? I appreciate any advice you could offer.