The 41-year-old Ronaldo is set to appear in a record sixth World Cup in June, a tournament expected to be the final major chapter of the forward's career.
"Wrapping up all this last World Cup with Cristiano (Ronaldo) winning it would be something amazing," Fernandes told Wayne Rooney in a BBC report published on Friday.
"I really hope we can make it happen, not just for Portugal, but for everything Cristiano gave to football and the world," the Portuguese midfielder and Manchester United captain said.
Ronaldo, considered one of the greatest players ever to have not won a World Cup, is the record scorer in international football with 143 goals.
The five-time Ballon d’Or winner was part of Portugal's Euro 2016-winning team and has lifted the Nations League twice.
Portugal's opening Group K game is on June 17 against the Democratic Republic of Congo, followed by Uzbekistan on June 23, with both games in Houston. They play Colombia on June 27 in Miami in their final group game.
The World Cup runs from June 11 to July 19 in Canada, the United States and Mexico.