online Ph.D

Yes you can do it from distance learning colleges like
IGNOU, LOVELY PROFESSIONAL UNIVERSITY, Nalanda Open UNIVERSITY, Madhya Pradesh Bhoj Open UNIVERSITY, Dr. BR Ambedkar Open UNIVERSITY, Amity UNIVERSITY and if you can afford you can try abroad universities for that also. Liberty University, Atlantic International University, Akamai University these three universities offers Ph.D. in online mode.

First you need to do M.Sc. Then only can go for Ph.D.

Yes, there are many universities in India that offers online Ph.D. programs. Some of them are mentioned below:
IGNOU, New Delhi. Indian Institute of Science, Bangalore. International Institute of Information Technology, Hyderabad. Karnataka State Open University, Mysore. Madhya Pradesh Bhoj Open University, Bhopal. Annamalai University, Annamalai Nagar (Tamil Nadu). .

Hello,
If you want to pursue Ph.D, you should do it by distance course, but not online. No colleges or university will provide you online Ph.D lectures, as it's not a child's play and if provide online lectures. You can get the desired knowledge and you can't even clear your doubts.