Hello Afrin
Yes, you can fill the NEET UG application form.

According to the eligibility criteria, candidates appearing for the class 12th board examination in 2019 are eligible to apply for the exam, considering, they meet the eligibility criteria.

In the NEET 2019 applcation form there is an option to fill the qualification exam code, you should select Code 01.

Code 01 is for Candidates who will take Class 12 board exam in 2019 and the results of such candidates are awaited. However, qualifying the exam is mandatory to be eligible for admission to MBBS/BDS courses.

Check the detailed eligibility criteria

https://medicine.careers360.com/articles/neet-eligibility-criteria

Good Luck!

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