"We're approaching this competition with a lot of hope," said the five-time Ballon d'Or winner.
"The preparation has been very good, tiring, because we have worked hard," continued the veteran Portugal captain who insisted he was "physically good".
"I am very positive, I believe things will go well and that we will put in a good performance.
"It's a very good generation... which will bring a lot of joy to the Portuguese people," the forward said of the squad around him.
"The most important thing is to start well, with the first match, then follow up with the second and third... finish top of the group and from there, take it one match at a time," he added.
Portugal open their World Cup campaign on June 17th in Houston against the Democratic Republic of Congo, before facing Uzbekistan and Colombia in Group K.
At 41, Ronaldo will be heading to his record sixth World Cup, but there are concerns in some quarters that his presence will prevent Roberto Martinez's strong side from flourishing.
Portugal played two friendly matches in recent days against Chile and Nigeria, winning both 2-1, but Ronaldo failed to score.
Portugal finished third in the 1966 World Cup and reached the quarter-finals four years ago in Qatar.
FIFA World Cup 2026
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
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