Please complete your Bachelor of Law (LL.B). Then enroll for Master of Law. with this you can complete the NET for law and then get enrolled as an assistant professor and after that you can complete you PhD (https://www.nls.ac.in/index.php?option=com_content&view=article&id=484&Itemid=44). This will enable you to become a professor of law ( along with the other eligibility criteria of age, teaching experience, publications etc). Dr.Rao, has mentioned, hence I am not repeating it.
With regards to ADR.
1.The Global Open Univeristy of Nagaland has a Masters
distance education program in ADR. The site also has an UGC approval letter. Please contact UGC and verify this.
2.The Indian Institute of Arbitration and Meidation deals with internation and domestic institutional ADR. This is the only insitute that is aoorived by the International Meidation Institute , Hague,Netherlands for IMI certification. You can contact them and get more information and think about a certification from them.
3.The International Centre for Alternative Dispute Resolution has centers in Delhi, Bangalore and Hyderabad.
You can also contact them.
4. The National Law school of India University, Bangalore has a special center - NIADR ( National Institute for Alternative Dispute resolution).
NIADR Centre Co-ordinator : Dr. V. Nagaraj
Registrar and Professor of Law, NLSIU
Tel. No. : 080-23160532/533
Email : firstname.lastname@example.org
5. Certificate course in ADR (http://www.arbitrationindia.org/pdf/brochure_cdm.pdf)
Post-graduate diploma in ADR, Inidan Law Institute, Delhi.
6. There are international law schools that offer Masters in LLM - Dispute Resolution
University of Portsmouth, Univeristy of Westminister,Enlgand.
International colleges also offer PG programs in ADR by distance mode also(https://online.qmul.ac.uk/programmes/international-dispute-resolution.htm)
So, bascially if you have a bachleor's and then a masters in law, it would be easier to get into the teaching faculty and simulatenously you can plan to get specific training in ADR as mentioned in (1 to 6).