As a foreign national, you can apply for enrolment in Ph. D. programme in India through the ICCR Programme of Ministry of External Affairs, Government of India. You should have sufficient proficiency in English language.
The average tuition fee that needs to be paid to pursue a PhD in India varies from INR 5,000 to INR 2, 00,000 annually (approximately). It generally varies for all the universities/ colleges in India, so make sure that you check the fee before you apply.