Dear Ms. Garner,
Thank you for posting your request on History Hub!
For an overview on how to begin your research, we suggest that you review NARA’s website about Native American Heritage as well as the FamilySearch Research wiki for Indigenous Peoples of the United States Genealogy.
We also suggest that you begin by assembling as much of the family tree as possible, as far back as you can go, and if possible, note locations. With that information in hand, you may then search the various Free US Indian Census Rolls 1885-1940 that are organized by Tribal Nation for mention of your family.
Please note that NARA only has custody of records created by the federal government that document those living on the reservations or being administered by the Bureau of Indian Affairs (BIA). If your ancestor was enumerated on Federal Census records as “white”, they may not be recorded in BIA records and tracing their Indigenous genealogy may be difficult.
We hope this is helpful. Best of luck with your family research!