Dear in response to you questions, as far as i know.

The upper age limit is 30 years.

The Syllabus is for bachelors level

and after qualifying the written, psychological and interview, you will be asked 3 options regarding your choice of departments / group of services. finally if your choice and merit corresponds then you are the one who will join the services.

Further if any mistake any senior can add from his side.

Take care.