Video report by Political Correspondent Libby Wiener
The Green Party vowed to create a "confident and caring Britain" at the launch of its election manifesto.
It includes plans to "reverse the privatisation of the health service" by introducing an NHS Reinstatement Bill.
The Green Guarantee also pledges to give people a referendum on the terms of a Brexit deal.
The party would also protect freedom of movement and immediately guarantee the rights of EU citizens.
Lucas: "We need hope now like never before"
Co-leader Caroline Lucas said: "The Green guarantee is about hope and we need hope now like never before."
"I can't remember a time in my own lifetime where the future has felt more uncertain - with Brexit, with accelerating climate change, with an NHS in crisis."
Ms Lucas also said Theresa May's pursuit of an "extreme Brexit" posed a threat to the country and the British public should have a "final say".
"Yes, there was a vote to leave, but it's not clear what that 'leave' looks like in practice.
"Which is why we say that it's right for the British public to have a final say on the deal, not just MPs as Theresa May would have it."
The Greens also pledged to cancel the Trident nuclear deterrent system as part of its goal to create a "safer world".
is the amount the party estimates would be saved over the next 30 years
Other plans set out include:
Safeguarding the environment including the introduction of an Environment Protection Act
Bringing forward proposals for a basic income, including a government sponsored pilot scheme
Providing access to education for all
The introduction of a shorter four-day working week with a maximum of 35 hours and scrapping zero hours contracts
Ending the gender pay gap and a requirement of a minimum 40% of all members of public company and public sector boards to be women
Reforming the tax system to include a wealth tax on the top 1% of earners
Read the Green Party manifesto in full