Yes! If you have done any mistake and you want to change the self declaration then when the correction window will be available you can surely change it without any doubt.

Apart from this you can made corrections in-

• Personal Details
• Choice of Medium of Question Paper
• Choice of Examination City
• Academic Details (Class 12 or Equivalent)
• Academic Details (Class 11 or Equivalent)
• Academic Details (Class 10 or Equivalent)

To know more about the correction window visit the link below:

https://medicine.careers360.com/articles/neet-application-form-correction-guide

I hope this answer helps.