The interview between Harris and Hallie Jackson was taped at the US Naval Observatory and aired Tuesday evening.
The Democratic US presidential nominee answered questions about President Joe Biden's poor debate performance before dropping out of the race, whether she would pardon former president Trump and the historic significance of her candidacy as a woman.
A tense exchange over Biden's poor debate
Ms Jackson asked Harris if she had been honest about Biden when she endorsed his re-election bid.
"You never saw anything like what happened at the debate night behind closed doors with him?" Ms Jackson asked.
"It was a bad debate. People have bad debates," Harris replied, referring to the face-off between Trump and Biden in June.
Ms Jackson then followed up, saying Biden's poor debate performance was the reason Harris is now the Democratic party's nominee.
"Well, you'd have to ask him if that's the only reason why (he stood down)," Harris said.
Ms Jackson again asked about Biden.
"I am running for president of the United States. Joe Biden is not - and my presidency will be about bringing a new generation of leadership to America," Harris said.
She then vouched for the president's political achievements and leadership.
"I speak with not only sincerity, but with a real, first-hand account of watching him do this work. I have no reluctance of saying that," she said.
Harris' plan if Trump prematurely declares himself the winner
Ms Jackson asked Harris what she would do if her Republican opponent declares himself the winner in the presidential race before all votes are counted.
"We will deal with election night and the days after as they come, and we have the resources and the expertise and the focus on that as well," Harris said.
In the hours after election day in 2020, Trump falsely declared himself the winner in the race against Biden, while votes still were being counted. The election was not decided until days later.
He currently faces allegations that he pressured officials to reverse the 2020 results and knowingly spread lies about election fraud.
When asked if the Harris team had considered a similar scenario on election day next month, the vice-president responded "of course".
"This is a person, Donald Trump, who tried to undo a free and fair election, who still denies the will of the people, who incited a violent mob to attack the United States Capitol... this is a serious matter," she said.
Would Harris pardon Trump?
Ms Jackson asked Harris if she'd pardon Trump if she becomes president.
"I'm not going to get into those hypotheticals. I'm focused on the next 14 days," she answered.
Asked if pardoning the former president would help unify the country, she said:
"Let me tell you what's going to help us move on - I get elected president of the United States.''
On the country being ready for a woman president
Harris also was asked whether the US is ready for a woman of colour to be its next president.
"Absolutely," she said, without hesitating. "...I think part of what is important in this election is not only turning the page, but closing the page and the chapter on an era that suggests that Americans are divided."
Ms Jackson then pressed Harris on why she has been reluctant to lean into talking about the historic nature of her candidacy on the campaign trail. Harris would be the first female president if elected.
"I'm clearly a woman.... the point that most people really care about is, can you do the job and do you have a plan to actually focus on them," she said.
When asked if she's concerned about sexism, Harris said she doesn't view her candidacy that way. Instead, she said her challenge on the campaign trail is making sure she can talk and listen to as many voters as possible.
"I will never assume that anyone in our country should elect a leader based on their gender or their race, instead that that leader needs to earn the vote based on substance and what they will do to address challenges," she said.
Harris later went on to discuss her agenda focusing on reproductive rights and abortion access.
