Could anyone tell me how to get a birth certificate for my mother Nelly Olsson, Grandmother Oline Olsson. My mother was born in Narvic and I believe my grandmother was born in Norway but not sure where.
You don't make it clear WHEN and WHERE each of these women were born. Any possible answer will greatly depend upon that information.
This is like asking for a birth certificate for John Johnssen born in Sweden...... virtually impossible to answer without much more information.
First you have to determine the WHEN and WHERE for the birth(s). Determine what records of births were kept in that location during that time period. Then find out HOW and WHERE you can get to see them and/or get copies.
This all ties into the other thread you posted about Oline's sister Ragna, doesn't it? It would probably be a good idea to look for Oline's birth records in the same area where her sister Ragna was born. That was noted in the 1900 Norwegian census page where Ragna was listed.