"It is a tough mission, that is clear, and the numbers don't lie, but we have the capacity, talent and we'll also have the organisation to complete it," Bento told a news conference.
Asked how he would deal with players' egos in a disjointed team which includes big names like Cristiano Ronaldo, Bento warned there would only be room in his squad for those committed to a tough mission.
"In this moment of difficulty it is completely forbidden for them to think as individuals first. The players have my admiration, but they will also have my demands and rigour in a short space of time," Bento said.
The 41 year-old coach was named on Tuesday to replace Carlos Queiroz, who was sacked for insulting anti-doping agents.
He will take charge of a side that is second from bottom in Euros Group H with one point from their first two qualifiers, having lost 1-0 in Norway following a 4-4 draw at home to Cyprus.
"One point from six is not good... we are in a complicated situation," Bento said, although he pointed out that Portugal have not missed a major tournament finals since the 1998 World Cup.
Bento's first games in charge will be the qualifiers on October 8 at home to Denmark and in Iceland four days later, with the side under pressure to win both games to give themselves a realistic chance of reaching the finals.
The Portuguese Football Federation (FPF) last week tried to persuade Jose Mourinho to take the job temporarily for the October qualifiers but the coach's club Real Madrid refused permission. .
"I don't feel weakened by the fact that one of the best coaches in the world, if not the best, was considered for national coach. I am proud to have been the choice right after him," Bento said.
His previous coaching experience was a 2005-2009 stint at Sporting where he was widely considered a success with four consecutive runner-up spots in the Portuguese League and two Portuguese Cups.
During that spell, Bento became known as a tough-talking disciplinarian, never shying away from clamping down on bad behaviour by his players, including top striker Liedson.
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