The Portugal captain netted a pair of penalties in a 2-2 draw with world champions France in Budapest to send his team through as one of the four best third-placed sides on a dramatic night in Group F.
France's fearsome forward line makes them favourites to win a third European crown at the pan-continental event, while top-ranked Belgium and a youthful England side will be major threats.
The 36-year-old Ronaldo is now six goals short of Iranian Ali Daei's all-time record of 109 international strikes.
Manchester City forward Torres was the star for Spain, who were as brilliant as Germany were bad. The result raises further questions about Germany coach Joachim Loew, who was already under pressure coming into this game.
Juventus forward Ronaldo is currently quarantined at his home in Turin after travelling from Portugal in an air ambulance following a positive COVID-19 test while with his national team for Nations League matches.
Ronaldo left the Portuguese team camp near Lisbon on Wednesday to fly back to Northern Italy on his private jet.
The Juventus forward who has been voted the world's top player five times played in Portugal's goalless Nations League draw against France but will have to sit out his national side's clash with Sweden on Wednesday.
Ronaldo broke the mythical 100-goal mark on the stroke of half-time, the 35-year-old Juventus attacker curling in a free-kick from 25 yards over the wall and into the far left corner beyond Sweden's stranded goalkeeper Robin Olsen for a memorable milestone in his trophy-laden career.
Portugal became the 17th nation to qualify for next year's multi-host tournament, which kicks off in Rome on 12 June, joining the likes of world champions France, Spain, Italy and England.
Cristiano Ronaldo has lost count of the number of records he has broken, the Portugal forward said after scoring the 700th goal of his career during a 2-1 defeat to Ukraine on Monday.
Captain Ronaldo, making his 160th international appearance, scored four as Portugal won 5-1 in Vilnius and strengthened their position in Group B after a sluggish start.
