There are several open source video editing software options available that you can use to edit and manipulate video files. Some popular options include:
Lightworks: Lightworks is a professional-grade video editing software that is available for Windows, Mac, and Linux. It offers a wide range of features, including support for 4K resolution, a large library of effects and transitions, and support for a variety of file formats.
Blender: Blender is a powerful 3D graphics and animation software that also includes a video editor. It is available for Windows, Mac, and Linux and offers a wide range of features, including support for compositing, keying, and tracking, as well as support for a variety of file formats.
Kdenlive: Kdenlive is a free and open source video editor for Linux that is designed to be easy to use while still offering a wide range of features. It includes support for multiple tracks, effects and transitions, and support for a variety of file formats.
Avidemux: Avidemux is a simple, lightweight video editor that is available for Windows, Mac, and Linux. It is designed for basic video editing tasks and supports a variety of file formats.
OpenShot: OpenShot is a free and open source video editor for Windows, Mac, and Linux. It is designed to be easy to use and offers a wide range of features, including support for multiple tracks, effects and transitions, and support for a variety of file formats.
No matter which open source video editing software you choose, be sure to read through the documentation and get familiar with the interface and features before you start editing your videos.