See there are no Central Universities which offers the course of BTech through lateral entry. So you can't do your graduation from the Central University. Now if you want to study in only the central universities, then you have to do the same on the entrances after 12th.

For Btech Lateral entry examination visit the link below:

https://engineering.careers360.com/articles/what-btech-lateral-entry-eligibility

Some of the top Government Lateral entry colleges are provided below:

• Bundelkhand Institute of Engineering & Technology, Jhansi
• Indian Institute of Carpet Technology, Bhadohi
• Institute of Engineering and Technology, Lucknow
• Kamla Nehru Institute of Technology, Sultanpur
• DTU Delhi
• Bharati Vidyapeeth College of Engineering, Delhi, Paschim Vihar
• NIEC, Shastri Park, Delhi
• GGSIPU - Guru Gobind Singh Indraprastha University , Dwarka, Delhi
• Engineering College, Idukki
• College of Engineering, Munnar, Idukki
• Govt. Engineering College, Kozhikkode
• Govt. College of Engineering, Kannur
• Govt. Rajiv Gandhi Institute of Tech., Kottayam
• Govt. Engineering College, Sreekrishnapuram, Palakkad

For more colleges, visit the link below:

https://engineering.careers360.com/articles/b-tech-lateral-entry-in-government-college

I hope this answer helps. All the very best for your future endeavors!