Why doesn't the git add command work?

Question

git

I don’t understand what the problem is ...
I connected Ssh keys,
did git clone on my PC
, went to my folder and try to add a file in it, but gives an error

Answer 1

I went to the github and
inserted this line into the console echo "# varfolomei" >> README.md
after that the git add command worked and finished the README.md file , it
turns out that if I want to add any file through the console, then I will need to write this command ?