Knowing where a letter comes from is not enough; you must know how it sounds. Sifaat are the qualities that differentiate letters sharing the same exit point.
Many Malayalam Islamic teachers (e.g., , Hashim Tani from Qatar, or Wayli Collection ) provide free PDF links in their video descriptions. Search for "Tajweed classes in Malayalam" on YouTube, and check the description box. Quran Tajweed Rules In Malayalam Pdf Download