It would be sensible to rent a car since the places are a bit far from each other. Ride-share services, buses, and other public transportation are available but might not be as convenient as renting a car. One can rent a car on an average of $30 a day, depending on the car type, and it takes approximately 20 mins from Long Beach Airport to Bellflower.
If you have more time, add a visit to the Historic Willow Springs Park, which features a great view of Bellflower and offers an outdoor picnic area. If you have less time, you can exclude the trip to Los Cerritos Center Mall or try to shorten the time spent shopping there.
Long Beach Airport (LGB) is the closest airport to Bellflower, California, located in Long Beach, approximately 7 miles from the city center.