Figen Murray, whose son Martyn Hett was killed in the 2017 attack, said more people needed to have the confidence to act in an emergency.
She has supported the Three Ways to Save a Life campaign in Manchester which trained more than 16,000 members of the public.
They were taught how to restart a heart using CPR or a defibrillator, how to stop severe bleeding, and what to do if someone is choking.
Figen and St John Ambulance want to see similar programmes rolled out across the country.
She said: “Before the Manchester Arena inquiry I didn’t think terrorism was something that could affect me and my family, and here we are nearly six years later.
“These skills are not on our radar as we go about our daily lives. But if something does happen, how good would you feel if you were able to make the difference between life and death?”
After learning during the inquiry how quickly a person can bleed to death, Figen joined a first aid lesson with survivors, their families and members of her legal team.
She now keeps a bleed control kit in her car and carries a tourniquet in her handbag.
She told the Daily Express that with knife crime on the rise, more young people should know how to stop catastrophic bleeding and the skills could be taught in schools.
Figen said: “It is something that has gained more importance after the arena inquiry. But also, what if you pass a traffic accident and people need help?
“What if you’re in a restaurant and someone at the next table chokes, and everyone panics but you have those skills? It’s that kind of stuff that’s really important.”
She added: “We need to be a more resilient nation. Just imagine if school-leavers learned those skills; in 10 or 15 years everyone entering adulthood could have those skills.”
The scheme in Manchester, launched eight months ago by St John Ambulance and BBC Radio Manchester, has delivered free training in schools, businesses and public spaces.
Broadcaster Louise Minchin joined a first aid demonstration on Tuesday. Praising the “clear and simple” training, she said: “It was really important for me to be here today to help raise awareness of this brilliant campaign.
“Manchester feels so much a part of my home – I was on air the morning after the arena bombing, I know people who were there, and I would have been there too were it not for my daughter doing her GCSEs and me telling her she couldn’t go.
“To be doing something that could make a difference is so important. Thank you to the St John Ambulance volunteers for the amazing work they do.”
Lucy Jarvis, 23, from Wigan, also joined the training session. She said: “I was involved in the Manchester attack in 2017.
“First aid is so vital, and on the night we didn’t have that – and if we had we would’ve been helped a lot faster.
“I’m so glad I did the training today. Knowing that if anybody ever needs my help, I’ll be able to help gives me such confidence”.
The campaign has now ended but volunteers in Manchester will continue to train at least 1,000 people each month.
Dr Lynn Thomas, St John Ambulance medical director, said: “Thank you to everyone who has taken the time to learn these simple lifesaving skills, and to our volunteers and staff for your commitment to giving people the confidence to deal with a health emergency.
“Born from a tragedy, the legacy of this joint campaign with BBC Radio Manchester can only be positive with thousands more people understanding essential first aid, and much more to come.”
Kate Squire, the BBC’s senior head of production for the North West and North East, said: “This has been a brilliant campaign that people living here have taken to their hearts, more than 16,000 of us will now have the skills to save lives to ensure a tragedy like this never happens again.”
