Manager Roy Hodgson announced his provisional England squad for the tournament on Monday and will hope to guide the country to their first major trophy since winning the World Cup in 1966.
And England will head to France with a 100 percent record in the European qualifiers, having won all their 10 games.
"I feel we've got a very good squad. It's probably the first time I've felt the squad is capable in any given game of matching any team," Rooney, the team's all-time leading goalscorer, told Sky Sports.
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"But obviously it's one thing having that, and another being able to do that consistently throughout a tournament.
"We've got players who can play anywhere across that front line. Myself, Jamie Vardy, Raheem Sterling, Daniel Sturridge can play out wide too. It's always difficult for opponents as well.
"We've had a good European Qualifiers campaign, but we need to make sure that we don't slack, that we keep going and keep pushing forward, and give ourselves every possible chance."
Rooney, who prefers playing as a striker, has acknowledged he might have to drop deeper into midfield where he has also been used by Manchester United manager Louis van Gaal this season.
With younger and faster talents coming through England's ranks, such as United teenager Marcus Rashford, Rooney was confident he can cope with any role in the squad.
"As a player you are always adapting. You adapt to your team mates, you adapt to the different coaches you are working under. It depends what the coaches want from you," said the 30-year-old, who scored seven goals in the qualifying campaign to overtake Bobby Charlton as England's top goalscorer.
"Throughout my career I've adapted to different situations and different teams I've played in, and I have no problem doing it. In football you need players who can play in different positions.
"I've always felt like I can play in different positions."
England face Russia, Slovakia and Wales in Group B of the 24-team tournament in France that starts on June 10.
England's Harry Kane speaks to Jamie Vardy after coming on as substitute
Image credit: Reuters
Rooney's comments that this is the first time he's felt an England side can compete with anyone at a major tournament during his time as a player is strange. Rooney burst to life at Euro 2004, a tournament where England went toe-to-toe with France and Portugal, and was part of the 2006 World Cup squad which, on paper, is the best squad the national side has taken to a tournament in recent times.
His aim is surely to engender some positivity around the setup, but it doesn't feel entirely sincere, despite the encouraging progress made under Roy Hodgson since the World Cup.
More revealing though are his admissions that he is happy to play elsewhere on the pitch. With Harry Kane, Jamie Vardy and Daniel Sturridge all selected, for the first time Rooney is not the No 1 striker. England have been so dependent on Rooney's fitness and form at every tournament since 2004, so this summer is a refreshing change.
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