Genealogy / Question about surname changes during immigration [11]

I haven't gotten the most welcoming responses on this site but Imma try again anyways cuz I don't like to judge a whole site on a few negative ppl....but here we go...

My grandma was born here but my great grandma was pregnant with her on the boat over lmao....they got here in 1920...

anyways, long story short. When they arrived at Ellis Island they made them change their surname to something more American....so my grandma's surname was changed to Vitek.

I am not aware of the original spelling of the name because my grandma has memory problems and don't remember exactly what is was...my question is this...is there any way I can find out? Or am I screwed?

I really would love to know more about her family that they left over there when they came to America...any help would be great, and plz enough with the stupid rude comments, its unnecessary.

Thank you to anyone who can help me in advance!

:)