Currently there is no standard number of tracks that producers have to record to make a pop song, although almost always there are more than two. For instance, original recorded tracks may include one for each instrument in a band and lead vocals plus perhaps one more for background vocals. How many tracks it takes to record a pop song depends on the equipment available.
If a producer is working with a mixing board to that has 24 input channels, he can record that many tracks simultaneously. More instruments or voices require more tracks. In addition, in post production, engineers can record and add tracks for string music and special effects and so on. When mixing down the final version of a song, they can also choose to leave out some tracks to produce the desired audioscape.
With digital recording now offering such high fidelity and programmable sound effects, producing pop music is much more about design, because producers aren’t limited to physical cabled connections to individual instruments. For example, the ability to use pre-recorded digital tracks such as MP3s means that instrumental tracks can be easily duplicated for bigger, deeper audio. Depending on the audio the artist and producer want to build, a simple pop song can start out with well over 100 tracks.