Dear Hitesh, 

Since you are already a graduate and have completed your Bachelor's, you can pursue the field of law through 3-year LLB course which will equip you with the credentials to become eligible for practice in the court of law. Besides this,  you can also join some short-term, diploma programmes in niche law courses like cyber law, etc. if you want to simply gain specialization and insights into the legal arena. However, it will not make you eligible to practice in the courts. 

Furthermore, many have this confusion as to whether or not they can simply do an LLM to pursue law. With respect to that, it isn't allowed. Only those who have an LLB degree can go for LLM. 

Coming to AILET (as marked in your question), it is conducted either for 5-year LLB or 2-year LLM admissions in the NLU Delhi. However, the best course of action for you would be to pursue a 3-year LLB degree since you are already a graduate. This will help you save on two years. You can go for DU LLB entrance exam, Punjab University three-year law entrance, etc. 

Hope that helps. 

All the best!