BMP388 itself is a very good digital sensor for pressure and temperature measurement.
small algebraic errors in the measured values can make several differences in further calculations.
Hence it is highly important to use the calibrated device. If the sensor you are using is within the standard tolerance then no need to do a recalibration.
While doing calibration you will need an analog transmitter, set it to zero. After this try to reduce the measurement error by adjusting the instrument.
I work in a field of instrumentation and often each of the sensor would need a "conformity certificate"
Pretty much cetifying that the sensor is staying within 10% margin of error for non critical application.
Would love to have some idea of the number of datapoints I should take.
[we are just using the barometer, and doesn't really use the temps]