John Gill Commentary Genesis 39:22

"And the keeper of the prison committed to Joseph`s hand all the prisoners that were in the prison; and whatsoever they did there, he was the doer of it." — Genesis 39:22 (ASV)

And the keeper of the prison committed to Joseph's hand all
the prisoners that [were] in the prisons
Who, as they were state prisoners, were a considerable charge; and this gave Joseph great honour, credit, and influence in the prison: and whatsoever they did there, he was the doer [of it] ;
not that he learned and exercised every trade the prisoners were of, to get a living by, which is the sense of some, as Aben Ezra relates; or that he in fact did everything that was done in the prison: but the meaning is, that he gave orders for the doing of everything, and there was nothing done without him; all that was done, as the Targum of Jonathan paraphrases it, he commanded it to be done; or, as Onkelos, all that was done was done by his word, that is, by his authority and command.