Hi, Malavika.

With 543 marks, your approximate neet rank will be between 12000- 14000.

It would have been helpful, if you would have mentioned your category as mostly all India ranks of neet are based on the different types of categories. 

For mbbs, the cutoff rank of 2018 for the categories are

General 6124

OBC 2514

SC 20687

ST 42037

For bds, the cutoff rank of 2018 is

General 61124

OBC 12514

SC 54965

ST 142037

Hope this helps.