The Manchester United striker was the first on the scoresheet as the Three Lions qualified for next summer's tournament with a 2-0 victory over Poland at Wembley
The Manchester United striker's seventh goal in six Group H games put the Three Lions on course for victory over Poland on Tuesday night before Steven Gerrard added a late second to seal a 2-0 win.
Roy Hodgson again opted for an exciting attacking line-up, which included the likes of Daniel Sturridge, Danny Welbeck and Andros Townsend, and Rooney feels that his side can head to South America with great optimism.
He told ITV Sport: "We have always remained positive. We have had a great belief in ourselves and from the manager. We have shown we are a good team and have got some fantastic young players.
"There is a good blend. We are excited and this is a good time to play for England."
The Three Lions came out on top against Poland to ensure that Ukraine would finish second, facing the uncertainty of a play-off, and Rooney was in no doubt that Hodgson's side had been good value for the win.
"We knew it was going to be a tough game," he added. "They had a couple of breaks and they could have scored but we played some great stuff and had the confidence to go on and win the game.
"A big part of our preparations was being patient and thankfully we got the goal in the first half. We fully deserved the win."