Hey dilshada.

Yes you can answer your NATA in July. NATA 2019 admit card is available on 2nd April by the COA ( Council of Architecture ) The COA had provided complete information about the exam in their brochure both for first and second attempt. The last date to submit application form for first attempt was March 11. Whereas the last date to submit application form for second attempt is till June 12. 

From this year i.e 2019 COA will conduct NATA twice a year 

1st Attempt on April 14

2nd Attempt on July 7

Hope I have cleared your doubt. Incase of any further information please feel free to drop a query. Have a good day!