My GY-MAX30100 pulse oximeter issue with Arduino Uno
There are 2 newer libraries you can try. I have used both with a MAX30102 and they work.

The first one is here: SparkFun_MAX3010x_Sensor_Library. There are several sketches included, and this one worked for me: Example5_HeartRate.

The other library I had success with is this one: Protocentral. It has a test sketch that writes the data to the serial port, but you can add Serial.println() statements to it to see if the data "makes sense".