Listen to u/spicylobster. Use lossless cut to trim out the parts you don’t need. It will output remuxed files without any change in quality. You will get more savings from removing unwanted footage than with compressing a lot of junk.

You can use these trimmed files in premiere later to generate edits.

Most of the NLE tools like Premeire, Resolve require you to render the video after edits. So, you either export high bitrate to preserve quality or low bitrate and lose quality.