Hindi is the most widely spoken Indian language in India, according to the CIA World Factbook. Though a nation with many official languages, Hindi is the most understood language in India other than English. Telugu is also an official language of India. If you are not confident with your level of English and can't find a class in Telugu, there are several ways to teach yourself Hindi online. You can also find Hindi and Telugu speakers in your community to help you.
Learn the Hindi alphabet. Hindi uses the Devanagari script, while Telugu uses its own writing system. The website Omniglot.com features information about written scripts of both Hindi and Telugu, so you can learn the alphabet and the sounds of Hindi. Write out the Devanagari script and the corresponding sounds in the Telugu alphabet to help you become comfortable with the pronunciations.
Once you have the basis of the alphabet, start learning words and phrases in Hindi. You can find several Telugu-Hindi and Hindi-Telugu dictionaries online, such as Dicts.info (see References).
Find a practice partner. The website MyLanguageExchange.com can help you find a Hindi-speaking language partner to help you learn Hindi. You may be able to find a partner who speaks Telugu and would like to exchange language practice. If you can't meet in person, set up some time to chat online or with Skype.
LiveMocha is a free interactive language learning website where you can find a Hindi-speaking teacher who wants to learn Telugu. This is a good choice if you want to do your language learning online and at your own pace. You can interact with Hindi speakers through the medium of Telugu and receive help in writing, pronunciation, listening and reading. Native speakers will check your work in exchange for your help with their language goals.
Watch some Hindi language films. Once you are ready for authentic materials, you will have no problem finding resources to help you become fluent in Hindi. India produces many films each year, in several languages. You can find films with Hindi sound and Telugu subtitles, so you can follow the story as you listen in Hindi. As you progress, watching Hindi films with Hindi subtitles can help you associate the Devanagari script with the spoken words in Hindi.