Hello,
Yes you can join Karnataka Government Polytechnic after twelve, but first you must satisfy the eligibility criterias below

• Candidate should be a citizen of India.
• Candidates should have completed at least 5 years of study in the state of Karnataka, including the qualifying examination
• Candidates should have passed Karnataka SSLC or equivalent examination with at least 35% aggregate marks.

You can get each and every details about the entrance tests and important dates from this link
https://www.google.com/amp/s/engineering.careers360.com/articles/karnataka-polytechnic/amp

You can also find the detailed fees structure for various categories in the above link


Hope it helps

JNEC Aurangabad

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Karnataka Government Polytechnic, Mangalore

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