I want to know how to get a progress-bar/seeker for the QMediaPlayer module on PyQt5... So on my music player application I can have a progress bar for the songs. Thank You in Advance
Your question is a bit broad, bit in general this is what you should do:

Create a QProgressBar
Create your QMediaPlayer
Listen to the currentMediaChanged() signal of your QMediaPlayer module; in your handler fetch the duration of the current media, divide by 1000 to get the length in seconds, set this as the maximum value of your QProgressBar; reset the progressbar.
Listen to the positionChanged() signal of your QMediaPlayer; in the handler fetch the current position; again divide by 1000 and set the value in your QProgressBar with setValue.

This should give you a progressbar that is automatically updated by the QMediaPlayer.
You may wish to disable the text in the progressbar as a percentage isn't really useful for a song playback. Unfortunately there doesn't seem to be an easy way to print the time in the progressbar.
Connect QProgressBar or QSlider to QMediaPlayer for song progress