Rohr will remain in charge of the three-time African champions for the next two-and-a-half-year after ageering terms on a new contract with the Nigeria Football Federation.
The German tactician has also been mandated to qualify the team to the 2022 FIFA World Cup in Qatar.
The former Gabon and Niger coach believes winning the AFCON 2021 title will be difficult, though not impossible.
“When you go to a tournament it is to win it,” Rohr told BBC Sport.
“We finished third in the last one, and everybody wants to progress. But we know also that it is very difficult to win this tournament because we are not number one in Africa.
“But it is good to have these milestones and ambition.”
The 66-year-old also stated that he is prepared for the task ahead meet the targets set for him by the NFF.
“My contract all the time is a risk because it is finished when we are eliminated from a competition – whether the Afcon or World Cup,” he explained.
“I took the risk already when I arrived, and it is still the same. But I am very optimistic, because now we have a team which is playing good football and I have confidence in my players.”
Rohr, who was appointed Super Eagles head coach in August 2016 guided the team to a third-place finish at the 2019 AFCON in Egypt.
He also helped the country qualify for the 2018 FIFA World Cup in Russia with the team failing to get past the first round.