Recently discovered I’m likely Jewish, how do I proceed in finding documentation?

I took a DNA test a while back and discovered that I’m like, 7% Jewish (ethnically). Upon talking to my mother about it she said growing up she knew she had a male relative on her mother side who escaped Europe during the Holocaust but that it was all very hush-hush and hidden from them. My grandmother and great grandmother have unfortunately since passed. Upon researching my grandmothers and great grandmothers maiden names I discovered there are MANY records for one of the names in general.

How do I go about finding out more information? Is there a place where I can search documents?

Thank you.