Sorry to say but you are not eligible to do MBA after passing 12th and without doing undergraduate degree, the minimum eligibility to do MBA course is graduation degree in any discipline

So firstly do graduation degree than you can apply for admission in MBA course

Eligibility for MBA
Candidate must have passed graduation degree in any discipline with at least 50% parks from recognized University

List of top MBA Colleges in India
Indian Institute of Management (IIM) Ahmedabad
Indian Institute of Management (IIM) Calcutta
Indian Institute of Management (IIM), Bangalore
Indian Institute of Management (IIM), Lucknow
Xavier Labour Relations Institute (XLRI)
Faculty of Management Studies (FMS)
Indian Institute of Management (IIM) Kozhikode
Indian Institute of Management (IIM) - Indore
S. P. Jain Institute of Management and Research
Indian Institute of Foreign Trade (IIFT)
Jamnalal Bajaj Institute of Management Studies (JBIMS)
Management Development Institute (MDI)
National Institute of Industrial Engineering (NITIE), Mumbai
Shailesh J Mehta School of Management, IIT Bombay
Symbiosis Institute of Business Management (SIBM), Pune
SVKMs NMIMS (Narsee Monjee Institute of Management Studies)
Institute of Management Technology - IMT
Tata Institute of Social Sciences (TISS)
Mudra Institute of Communications, Ahmedabad (MICA)
Indian Institute of Technology Delhi (IIT Delhi)
Xavier Institute of Management Bhubaneswar
Symbiosis Centre for Management and Human Resource Development (SCMHRD)
Vinod Gupta School of Management (IIT Kharagpur)
Rajiv Gandhi Indian Institute of Management (IIM) Shillong
Indian Institute of Technology Kanpur (IIT Kanpur)
K. J. Somaiya Institute of Management Studies and Research
Institute of Rural Management (IRMA)
Symbiosis Institute of International Business (SIIB)
T. A. Pai Management Institute, Manipal (TAPMI)
Symbiosis Institute of Business Management Bangalore
International Management Institute (IMI), Delhi
Great Lakes Institute of Management
Indian Institute of Management (IIM) Ranchi
Institute of Management Nirma University
Indian Institute of Management (IIM) Raipur
Indian Institute of Management (IIM) Tiruchirappalli
Indian Institute of Management (IIM) Rohtak
Indian Institute of Management (IIM) Udaipur
Goa Institute of Management (GIM)
Indian Institute of Technology Madras (IIT Madras)
Xavier Institute of Management & Entrepreneurship
Symbiosis Institute of Management Studies (SIMS)
FORE School of Management, New Delhi
LIBA (Loyola Institute of Business Administration)
Birla Institute of Technology and Science (BITS-Pilani)
Prin. L.N. Welingkar Institute of Management
Indian Institute of Technology Roorkee (IIT Roorkee)
Lal Bahadur Shastri Institute of Management (LBSIM)
ICFAI Business School
Xavier Institute of Social Service