Hey!

Since you haven't provided more details regarding which application form you are referring to in your question, I would tell you in general sense. If you've been asked to upload your marksheet in any application form then you have to scan an original marksheet. So, there is absolutely no issue if you have scanned an original marksheet. Just make sure that the scanned image is clearly visible and understandable. In any case, if anyone doesn't have the marksheet which is provided by school then one can provide the DigiLocker downloaded marksheet too.