We remember asking this very question ourselves. We have recently been recommended for approval by adoption panel and although most people we know are aware we are going through the adoption process to some degree or other, we've deliberately not told everyone and we're two years in now! Although from the people we have told, they have all been genuinely fascinated about the adoption process. In some cases constantly asking if we have any updates or what happens next etc. We even had a chat with our local police officer who it turns out was herself adopted long ago. It made us realise that more people are adopted than we realise or know somebody that was previously adopted or is going through the process now.
We guess it just depends on who you feel comfortable telling. It boils down to your individual situation. It's both your adoption journey and your adoption story.
We are lucky that we haven't really had any negativity as such which has been great, but even if one or two people are negative it's only out of ignorance - and there's a whole raft of information out there to help them with that. (various books, Youtube, National Association of Therapeutic Parents, etc. etc.)
The stages of adoption (as we understand it) are:
Pre-Stage 1 - Information about adoption
Stage 1 - References, checks and introduction courses
Stage 2 - Numerous home visits or online sessions with social worker plus more courses
* Adoption Panel *
Stage 3 - Matching with the right child
* Matching Panel *
Stage 4 - Moving In!
A tip for Stage 2 - always be totally honest with yourself, each other and your social worker. The more you put into this stage the more you'll get from it. We have learnt a LOT about each other during Stage 2 - right back to each others childhoods and early adulthood - and now feel more connected and ready to adopt than ever before!
Good luck!
Edited 17/02/2021
"If you imagine it, you can achieve it. If you dream it you can become it." - Quote by William Arthur Ward