Hello,
Yes class 12th mark sheet is required to be uploaded in DUET application form. Due to corona virus or COVID-19 the DUET 2020 exam is postponed until further notice and so is the application form. So mostly the results will be declared before the application form for DUET is released. Please click the below link to know more about DUET 2020 exam.
https://www.careers360.com/exams/duet
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