Just a follow up on Robynne and Michael, atDNA will, indeed, only go back 6 to 8 (pretty much max) generations.
One activity I have done is to have my mtDNA and my brother's Y-700 DNA done at FTDNA. I have also joined 'groups' on FTDNA to learn more about what we can and cannot determine with DNA. I've also taken a genetic genealogy (GG) course through our local historical society and a full day workshop with Blaine Bettinger earlier this year (pre Covid19). I am still learning!
One of the FTDNA groups that I joined was the Baldwin surname study. A wonderful man, Donn Devine, JD, CG was manager for this surname study because his wife was a Pennsylvania Baldwin descendant. Donn died a year ago at 94 years and I am glad I kept his emails to me. He listed my brother with the CT Baldwins. Following the GG course, I spoke with the instructors and when Covid slows down (and it will someday) we are going to write a 'proof' on the 10 or so lines that I received from Donn to trace back to the 'common ancestor.' This is not a sure fire way to confirm. This Y DNA will assist with tracing back to the common ancestor via these various Y DNA lines; however, it is ONLY good for this particular Baldwin line and not other male grandparents.
Again, classes have helped a great deal to understand atDNA, mtDNA, X, Y as to their strengths and weaknesses.