Why Satellite tracking software predicts where a satellite will be by propagating its orbit mathematically, and that requires the orbital parameters known as Keplerian elements (often distributed as two-line element sets, or TLEs). These describe the orbit's size, shape, tilt, orientation and where the satellite sits along it at a given epoch time. Combined with your grid square or latitude/longitude and the current time, the program computes azimuth, elevation, pass times and Doppler shift.
Watch out Transmitted power tells you how strong the signal will be but says nothing about where the satellite is, and a past zero-Doppler observation is an output of the geometry rather than the data the program needs to start with.
Tracking needs orbit math: Keplerian elements (TLEs) in, azimuth/elevation and Doppler out.