As an Urdu speaker, I have found the following roadmap the most effective in learning Hindi:
1. The first 20 lessons from the Ukindia Learn to Read Hindi Website. My recommendation is to pick up the basics and ignore anything that seems to complicated or is mentioned only for the sake of completeness. For example, Hindi has letters for compound sounds of which only a few are commonly used. The beginner can ignore the rest for a later stage.
2. Use the excellent Devanagari Script Tutor developed by the School of Oriental and African Studies (SOAS) if you wish to see how to draw/write the letters and hear how they are verbalized.
3. Use the New York University Virtual Hindi Website to begin reading. The graded stories from very easy to difficult are ideal to learn as you go. You can hear the stories as well to correct your pronunciation. The meanings of unfamiliar words are also provided.
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