This video shares a lossless way to convert video formats/containers with a powerful video converter. Get the software here
https://www.videoconverterfactory.com/tips/change-video-container.html
Few tips when making lossless conversion
The lossless video conversion is also called remuxing or repackaging, meaning changing the container format only without re-encoding. Only in this way can you achieve real lossless conversion.
There are some requirements, though.
1. The encoder used in the source video is supported by the target container format;
2. The video parameters, including bitrate, resolution, aspect ratio, etc., cannot be changed;
3. The video cannot be edited (trim, crop, add watermark, and so on) before the conversion;
Luckily, the software will automatically smart fit the best settings for your video conversion, so you don't have to worry about it too much. However, you can still manually set the parameters in the parameter settings for more accurate conversion.
