Tally 7.2 was designed for older operating systems but can still run on modern hardware with adjustments: : Windows 98/2000/XP (Native).
The "free download" part of your search is the red flag. Here is the truth about Tally 7.2 licensing: tally 7.2 release 1.41 free download
Respect the legacy. Protect the present. Tally 7
Before Tally.ERP 9, before TallyPrime, there was Tally 7.2. Released in the early 2000s, version 7.2 was the workhorse of Indian SMEs (Small and Medium Enterprises). tally 7.2 release 1.41 free download
Here are some potentially useful papers and articles related to Tally or accounting and inventory management: