Hello Nidhi,
National Aptitude Test in Architecture (NATA) will be conducted by the Council of Architecture (COA) tentatively in the last week of april, 2019. 
The paper will consist of two parts, part A will consist of questions from the  mathematics and the general aptitude subjects. Multiple chice questions will be asked in part A and have to be answered in online mode.
Part B will include drawing based questions and have to be answered in A4 sheets.
You can go through the link below to check the detailed syllabys-

https://engineering.careers360.com/articles/nata

Good Luck!