How to recover silver from the diluted nitric acid solution which
content silver, copper & etc by electrolysis?

If there are no other metals like gold mercury or gold in your
mixture, you could simply drop copper sheet into solution and then
collect the sediment (will look like black powder) and melt it.
You could do electrolysis too, with low current and proper stirring.
Silver will be reduced first, copper afterwards. But you will have to
take samples of your solution from time to time, to test how much
silver is left.
I think the first method is much simpler.

Thank you for your comment. But could you lead me the way to set up
the electrolysis (how many voltage? what is the current?)in order to
extract the silver?