Hi Renuka, one of the books I have been suggested is the sanskrit Svayam shikshak by Shripad Damodar Satvalekar, go for one literature book like the Valmiki Ramayana or Kalidasa's literature.
Use other online resources like YouTube and Google Translate as well. I suggest also checking out the NCERT books once you get a clear base in sanskrit for vocabulary building and stories
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