Dear Aspirant,

All the three courses have different target groups and utilities. Here are the details for you to get a bigger picture:

1. NTT : This is also known as Nursery Teacher Training. This is an undergraduate  diploma course in education targeted at training individuals to deal with preschool and nursery curriculum. This is important for child's growth. It is responsible for laying the foundation of future courses and learning experiences for the child and it is focused on training the teacher to enable a controlled experiential environment for the child. This is an important course for the teachers, so that they understand their role properly. The time duration of the course in 1 year and can be done after completing 10+2. The job profiles which can be taken up after the completion are: Teacher- Nursery,  Assistant Pre-Primary Teacher, NTT or B.Ed Teacher, Nursery Manager or in-charge and Home Tutor. The course can be done Part-time, Regularly and in correspondence. Both English and Hindi languages are used.
2. NPTT: These are primary school teachers. This is also a diploma course of 2 years which can be pursued after 10+2 or equivalent. This course focuses on training the teacher to understand that primary is the stage in child's life where there is maximum development. This is the experience the child always remembers and therefore, a primary teacher plays an extremely important role in the life of a student. The program focuses on lesson planning, making a time-table, preparing materials for class and engaging students in artful materials. The course gives a keen insight into teaching a broader age group of 2-12 years and has been designed not only for aspiring and professional teachers but anyone associated with pre and primary teacher training couse.
3. B.Ed. : This a degree unlike the other two and is not confined to a specific age of children. For joining this one should be a graduate from a recognised board or university with at least 50% marks. The person can later move on to become not just teacher but with masters the HOD or Principal and Vice Principal. The duration of the course is two years and there is 100% job placement after the same.

You can also go check their website for more info: https://www.ipwdelhi.com/teacher-training-course-delhi

Hope this helps. All the best!