Hi OP, here is my ancestry story.
So my dad and I did the DNA testing because he wanted to know a, what happened to 2 sisters who got adopted and if there were any more b, whether his dad was really his dad.
Well the DNA results told us SFA other than 4th cousins and that we were irish/scottish and german which we already knew.
However, what I did do, was enter my family tree into Ancestry and that helped a lot because other people had done family trees too. Every time I entered a name, a 'match' would come up (it looks like a leaf). I could then see the source of the match, who their kids were, their parents etc and build my family tree.
I also used the national records of Scotland (we are Scottish). Searches are free but certificates need to be paid for and I spent rather a lot of money TBH.
I entered my late grandmother's surname and places of birth. It brought up a few potential children and I had to buy a few certificates but I found one sister who had sadly passed away but we were able to reconnect with her children - my cousins. Which was lovely.
Then we tried to track down the other sister but could not find her at all. I wondered if her name had been changed / if she had been adopted so I contacted the NRS directly and they kindly did a search by mother's name and found the other sister, who has also passed away but again I have reconnected with my cousins.
Through using the NRS and looking at valuation rolls, census records, birth and death records, I have also been able to establish that there may be a 3rd aunt but as her name is different and she was adopted, there is not way of knowing for sure unless she also does a DNA test and I'm not going to ask an old lady in her 80s who has never met me to do that. Not sure how to go about it to be honest.
I have also established that we are descended from royalty on both sides.
My great great grandmother was seemingly a prostitute as my GG grandfather is listed as the father of several children by several women and these women all lived in the same house but with different names.
There is a lot of illegitimacy, adoptions and suicides on my fathers side. My mothers side dont seem to have had any issues other than war and famine.
So stick with ancestry for the family tree rather than the DNA.