The first thing to do is to get a DNA test from a reputable DNA testing company.
Most important, contact any other relatives from the side of your family that the information about Native ancestors came from. If its true, someone might have some information about the names of your ancestors, which is critical in trying to see if they were ever enrolled in either Tribe.
Then contact both the Blackfoot and Cherokee Tribes (they are both Federally Recognized Tribes) via their websites. Both Tribes have divided into several sub-groups so you'll have to keep digging, but don't get discouraged. If you are courteous and respectful, they will check to see if you have an ancestor in their Official Rolls once you have a name to go on. Some Tribes are sensitive about this as they do not want to expand their Rolls further, fearing to share the few benefits they get from states and Feds to people on their Rolls.
-Good Luck in your Search!
Dear Ms. Schiafone,
Thank you for posting your request on History Hub!
We 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. Since the Cherokee were an Eastern tribal nation and part of the early removals, the U.S. National Archives (NARA) has custody of records for the tribe that date back to the 1830s when the first removal rolls were compiled. The tribes that collectively are known as the Blackfoot were located further west and north and into Canada. Since the U.S. government did not interact with that tribe until the mid-19th century, and even then did not begin to compile detailed individual records until the 1880s and later, NARA’s records also would reflect that.
To learn more about the records in the custody of NARA that pertain to individuals, please review the web page for Researching an Individual or Family. With the names you are able to compile, we suggest searching the various the Indian Censuses that are organized by tribal nation and are available for free.access at https://accessgenealogy.com/native/free-us-indian-census-rolls.htm
When embarking on Native American genealogy, please note that the records in the custody of NARA often only detail those living on the reservations or being administered by the Bureau of Indian Affairs. If an ancestor was native yet left the reservation, they will not be recorded in NARA’s records and tracing their genealogy may be difficult.
We hope this is helpful. Best of luck with your family research!
[Information provided by Cody White, Subject Matter Expert]