If you sometimes have trouble opening and playing certain file formats e.g. for videos, free and open-sourced VLC software makes it easy to play almost any file format you throw at it.
To download the app, which works with Mac, PC, Linux, Android, and iOS, and states that it doesn’t deliver ads or engage in user tracking:
– Go to https://www.videolan.org/vlc/features.html
– Click on the appropriate Operating System.
– Read the details and click on the orange download button.