I recently found out that my Grandparents were born Jewish. My grandfather came from Greek Jews. Am I then a Sephardic Jew? My father is not Jewish, but both of my mother’s parents are.
Thank you for your question.
How lucky you are! To be part of the Jewish people, although it comes with a decent amount of responsibility and obligations as any opportunity does. However, it entitles you to the privilege of having a special portion in the world to come for eternity, the privilege of being part of the resurrection, and having a special closeness to G-d, and partaking in all the blessings that are spoken about in the scriptures during the time of the Messiah.
Being naturally Jewish is dependent on maternal lineage, meaning that if you mother is Jewish then you are Jewish (and your mother is Jewish because her mother was Jewish). Regarding which custom to adopt, you would technically be considered Sephardic, however you can adopt the customs of the community that you are living with, and if they are Ashkenazi, and this is what you are more comfortable with, you can take on those customs.