See if you have your Application number/registration number and if all the details you have uploaded is ok, then there is nothing to worry about the Confirmation. Although its always advisable that you should keep it as a document. But as you have lost it , you didn't have to worry a lot.

If you want to get your registration receipt then you can try to trace the Softcopy of the registration receipt if you have any in your pc or smart phone. This way you can get it again.

For NEET revision strategy visit the link below:

https://medicine.careers360.com/articles/revision-strategy-for-neet

I hope this answer helps. All the very best for your future endeavors!