Re: what is the exact meaning of this sentence.
We had hardly sat down to the supper when the phone rang. (We had only just sat down and were about to eat supper or had only just started eating when the phone rang. )
We can't stop for coffee now, we've hardly started. ( We can't stop for coffee because we've only just started.)
'Hardly' has the idea of 'almost not'.
Please do not edit your question after it has received a response. Such editing can make the response hard for others to understand.