Hello Namrata

The eligibility criteria for MDS NEET -

Qualification - one should pass BDS  degree.

Registration certificate - one should have a registration certificate issued by DCI.

Internship - a 12month of rotatory internship is must.

There's no age limit clarified by authorities.

Now preparation, for preparation it's always better to give more importance to topics which have more weightage, and the topics you are good at.

And also it's better to solve previous year question papers, it will give you a good idea of time management and the questions which are from same topic and repeating most often.

There are many books, dental pulse is the top rated and most suggested book ,it enhances your knowledge to a very high degree.

I hope it helps