Nicola Sturgeon has said she is the only politician in this election campaign offering serious leadership.
Pressed repeatedly on her party's record in government on education and health, she said progress had been made but insisted there was more to do.
She said it was a "serious time" as Scotland recovered from the pandemic, and stressed her view that the SNP was the only party with a proper plan.
The other political parties were all vying for second place, she said.
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Ms Sturgeon told The Sunday Show that politicians tend to claim every election is the most important but this time it was "probably true", she said.
"I am the only candidate for first minister that is not just talking about recovery in this election but has put forward a serious plan but to bring about that recovery," she said.
Ms Sturgeon said she would "challenge" the claim that her party had not kept promises it made at the last election.
On the attainment gap in education, Ms Sturgeon said "we haven't yet done enough", but pointed to some examples of progress and said there was more work to do if re-elected.
And she said work was ongoing towards delivering improved cancer services promised five years ago.
On an SNP pledge from 2007 to scrap the council tax, she said there there had been no consensus in parliament on what to replace it with. She added that the tax had been reformed to be more progressive.
Ms Sturgeon added: "We are not saying there are not big challenges to address in this country, but we are the only party actually doing the work and putting forward the plans to actually do that - and that's the choice people have on Thursday.
"Do you want to vote for parties who are vying for second place, openly saying they've got no plan for government - or do you want a serious first minister, an experienced first minister, leading a government that is serious about tackling the challenges?"
When interviewer Martin Geissler suggested that Ms Sturgeon had had "a harder year than any of us", she said "No, I haven't.
"Sure, it's been really tough - but if you're an individual who's lost somebody to Covid, or a business person who's seen your business go to the wall that's a lot tougher."
Asked what toll the last year had taken on her personally, Ms Sturgeon said: "Every single day for the last year, I've had to take decisions where it has felt like weighing lives on one hand and jobs on the other.
"I've had more sleepless nights in the last year than I've had in my entire life combined and it's been tough.
"But I've learned a lot, I think I have a lot of experience now that is needed to drive the country through the remainder of this and then hopefully to a better future."
SCOTLAND'S ELECTION: THE BASICS
What's happening? On 6 May, people across Scotland will vote to elect 129 Members of the Scottish Parliament (MSPs). The party that wins the most seats will form the government. Find out more here.
What powers do they have? MSPs pass laws on aspects of life in Scotland such as health, education and transport - and have some powers over tax and welfare benefits.
Asked if she was re-elected if she would serve for another five years, she said: "I am going to do the job people elect me to do if they elect me to do that job.
"Elections are like job interviews, it would be absurd if I was to sit her and say 'give me the job but then I might not do it'."
She added: "I will serve the term, I'm not going to start thinking about future elections before I have won this one."
Ms Sturgeon concluded: "This country really needs serious leadership because it's a serious time and that's what I offer and it seems I'm the only one in this campaign offering that."
This was a confident and bullish performance from someone who seemed ready to take on any challenge.
Nicola Sturgeon firmly stated her own lines and opinions and quickly batted back any questions or assertions she didn't agree with.
There seemed to be an over-riding theme - "give me the ability to get back to work", as the first minister put it herself.
She hit out at her opponents - saying: "Do you want to vote for parties that are vying for second place?"
The SNP leader attempted to set out that she alone had the confidence, skill and judgement - "a serious first minister with a serious plan for government."
Part of getting the job done revolves around Covid recovery - but also about the wider job left unfinished.
It was put to her that there was still work to be done in closing the attainment gap. Ms Sturgeon refused to acknowledge failure - saying progress had been made but "the job is not done".
On the wider plan for independence, Covid recovery and constitutional change are portrayed as two sides of the same coin. "Recovery is not a neutral concept," the first minister said - making it clear there should be a choice of what kind of country you want to have.
It's obvious this has been a tough job - the leader said it had taken its toll, adding there had been more sleepless nights in the past year than any other.
Even though autumn 2024 will mark a decade in power if re-elected, Ms Sturgeon said she had the appetite for it and "would serve the term".
There's a real attempt to demonstrate that appetite and energy - perhaps to ward off detractors who accuse the leader of dallying on independence.
Douglas Ross, the Scottish Tory leader, was also interviewed on Sunday. He said "of course" the prime minister should resign if he was found to have broken the rules over who paid for renovations to the Downing Street flat.
Asked if Mr Johnson had not come to Scotland because he is a "liability", Mr Ross told the BBC's The Andrew Marr Show: "The reason he has not been to Scotland is because I am leading the campaign here.
"I am the one taking the fight to the SNP to try and get the next Scottish Parliament laser-focused on our recovery and rebuilding, to try and ensure we see the investment in our NHS, in our police service, in our education system.
"All these things that are under threat at the moment, we can actually have a parliament focused on these issues if we can stop a second SNP majority."
Scottish Labour's leader Anas Sarwar admitted in a radio interview on Sunday that Labour's "glory days do seem very, very far away", and that his goal was for the party to be a "credible opposition".
He added: "I'm not projecting I'm some kind of superhero that's going to turn our 14% vote share in eight weeks, when I took over leadership, into us being in government."
And Lib Dem leader Willie Rennie told broadcasters on Sunday that his party would "make the difference" between a Holyrood parliament focused on recovery rather than an independence referendum.
He projected that his party would gain seats at the polls on Thursday.
"I never put any limits on the number of seats that we're going for. I just know we're going to grow with the number of seats that we're going to gain in every part of Scotland," he said.
The Scottish Greens have previously insisted that they have not had discussions with the SNP about forming a coalition after the election.
The party's co-leader Lorna Slater said there was a "huge amount of distance" between the parties on key policy areas, including climate change.
The Greens have urged voters to make climate change their priority this election, and "vote like [their] future depends on it".
What are the parties promising you?
Use our concise manifesto guide to compare where the parties stand on key issues like Covid-19, independence and the environment.