Hi, Since India is an agrarian country, this field will never run out of job opportunities.
It is a 4 year course.
Some of the important topics to consider are:

Agronomy
Plant Genetics
Soil Science
Entomology
Agricultural Economics
Agriculture Engineering
Agricultural Meteorology
Horticulture
Biochemistry
Physiology
Microbiology
Computer Education
English
Physical Education
Animal Products

Lots of Government as well as Private job opportunities are present in front of Graduates. Talking about Government jobs, State Agriculture Departments recruits Graduates to fill up Officer level posts. Government Banks also recruits Graduates to fill up Officer level posts.

Hope this helps.
Good Luck.