I am into 2nd month after hair transplantation. Is it safe to apply lemon juice to get rid of the dandruff?

It is best to follow the instructions or recommendations of the doctor who has examined you. If you are worried see another doctor for a second opinion.

Some men in their early 20's go on to have hair transplant surgery. There is no rule. It is best to consult with a doctor regarding your specific goals and your Master Plan.

Donor hair (permanent hair) is not affected by Propecia (finasteride). If you have hair loss issues on your donor area it probably means there is something else going on.

Congratulations on working towards restoring your hair. Using hair transplant with the strip method with leave a scar at the back of your hair and affect your tattoo. The latest FUE methods with Smartgraft tend not to leave any noticeable scars. Am not sure why you are going to India when there...

FUE is just a harvesting method. It does not relate to results. Keep in mind FUE is done with the head shaved. FUT is not.  This may be an issue if you are a woman.

Your photos shows hair on your scalp. You don't provide a "before" photo to compare with. If you were bald it looks like a good result.