No, you cannot extend your India Tourist Visa while in India. In India, tourist e-Visas and regular tourist visas cannot be extended while you are in the country. If you want to stay longer, you will have to leave India and apply for a new visa from abroad. Staying past your visa's expiration date can lead to fines, penalties, and you might not be able to get a visa in the future. In unusual situations, like a medical emergency, you can ask the Foreigners Regional Registration Office (FRRO) for help, but getting approval is not certain.