to be fair to Modi, India can not change pakistan's strategy of using terrorists against India.
only thing Modi can do is increase the cost of pakistan sponsoring terrorist attacks against India,
1. Ask Indian Army to unleash hell on border, involve 155 MM guns, for weeks if necessary months.
2. Try to expose pakistani terrorist policy diplomatically each and every international forum.
3. Stop people 2 people contacts, stop samjhauta express or any other trains, no visa for pakistani politicians or filmy persons.
4. Go full support for Balochistani or Sindhi separatists. Armed and Political.
I dont think India has any other options available to act against pakistan, the no go option is full frontal war that should be avoided.