If you have learned how to download your raw dna data file from your testing company, then you should also upload to GEDmatch.com, here you can find matches who also uploaded from the other 2 sites mentioned below (MyHeritage, FTDNA) but added in this mix are matches from 23&me, and ancestry who have done the same. On my gematch match list, anyone who has a tree linked to their GEDmatch acct. from wikitree have a link to their tree, which might aid in your quest. You can then go from the profile of a tested person, and cross check their other other DNA matches from different lines of their tree. Search Angels are top-notch, and will help!
Last year, in October or so, the daughter of an adopted 1/2 sibling of my father’s showed up on my ancestryDNA match list. So, she is my 1/2 1st cousin! My aunt, who is a full sibling to my father, and 1/2 sibling to her father, has also tested, and the shared amount of DNA between all of us confirms this relationship, fitting within the common, proper ranges for our relationships, on top of our collective shared matches, and some adoption paperwork, family is confirmed. Her father, who was adopted, has not tested, but that is ok, since she is still a very close match. He does not want contact either, and that is fine. Maybe someday?
I myself, have found a new 1/2 sister, confirmed with DNA! Very exciting to locate relatives who you never knew existed, like a 38 year old baby grown up sister! Dna will find your family! It may not find open arms, but chin up if you encounter the negative! Not everyone will be that way! People who aren’t adoptees are just as suceptable to negative responses or no responses from matches. Good luck!