Hello Ankit,
Hope you're doing well. It's great that you'd an MBBS seat at Government Medical College.
However now if you wish to take admission in Engineering college then you're definitely allowed for that.
There's no such restrictions that you cannot withdraw and take admission in another college.
For predicting colleges based on your JEE rank visit- https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer
Hope you find this helpful.
All the Best for New Beginnings!
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