CBSE 12th

Hi Krishna,
Popular entrance exams after class 12th PCMB include:
All India Pre-Medical / Pre-Dental Entrance Test (AIPMT)
All India Pre-Veterinary Test (AIPVT)
National Level Medical Entrance Exams like AIIMS, CMC-Vellore, CMC-Ludhiana, COMED-K, JIPMER, AMU (MBBS), BHU Medical and many more.
EAMCET-Engineering Agriculture and Medical Common Entrance Test.
AGRICET-Agricultural Common Entrance Test
HORTICET
ICAR AIEEA UG

Hi Ayush,
Easy or difficult will depend on you. If you are good with numbers or maths and enjoy learning about finance, accounts, on the whole, it shouldn't be too difficult. Knowledge of computers will only add to your advantage.

Hi Ankit,
You cannot appear for TIFR exam after class 12th.You must either complete your Bachelor's degree or must be in the final year. Please check TIFR website for details.

The admission in the engineering colleges of Pune is based on the JEE Mains score. Admission into B.Tech programme is also done through MH CET. Some universities also conduct their own entrance test for providing admission such as Bharati Vidyapeeth University conduct BVP CET, Symbiosis International University offer admission through SET (Symbiosis Entrance Test).
I hope, this may help you.

Qualification
Minimum Eligibility to Apply
12th-45%
Additional Details
Mandatory Subject : Mathematics/ Business Mathematics
Aggregate of one language and three best elective subjects would be considered as best four subjects (BFS).
Environmental Education (ISC), Fine Arts, Graphic Design, Painting, Dance, Music, Physical Education, Home Science, Engineering Drawing and all other vocational subjects are not considered as BFS.