"Priya" is likely a specific weight or a modified version of the original Janani font. Because the original designer(s) of many classic Tamil fonts are often small independent foundries, these fonts are not open-source. They are proprietary software.
If you are looking for this specific font or general Tamil fonts for creative work, you can follow these steps:
Direct download links for a specific font named are not available through major official repositories like Google Fonts or the Microsoft Store . This font is likely part of a private or "exclusive" collection often shared via third-party design communities or bundled within specific Tamil software tools.