Hello student, if you have completed class 10th then you can take admission in diploma courses in polytechnic. You can also do diploma after passing 10+2 but generally people go for degree after 10+2. If you pass entrance exam for the diploma college that you want to apply (like Delhi CET, AP JEE, Punjab PET, Odisha DET) which depends on the state you live in.  Then you will get a seat according to merit list based on your marks. You need minimum 50% marks to be eligible for entrance test. Diploma in Civil is a 3 year course after which you can apply for jobs or you can get admission in degree program by lateral entry.

For more details visit - Polytechnic - Course Details, Fees, Eligibility, Admission Process, Career Scope & Jobs, Syllabus (careers360.com)

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