Even better – avoid them entirely.
Are you planning to post this on a , a movie blog , or Letterboxd ? I can adjust the formatting to fit the platform.
“Oh.My.Kadavule.2020.Tam.DS4K.1080p.10bit.WEBRip” is a release label from unofficial sources. “DS4K” is not a legitimate quality marker. The file, if real, would be a 1080p 10bit HEVC WEBRip – but downloading it is both illegal and risky.
Yes, using FFmpeg or HandBrake. However, you lose the color gradient benefit and re-encoding reduces quality further. Better to download an 8bit file directly.