Stop buying shit. Consumption = Emissions. Drive as little as possible. Cars = Emissions. Adjust your thermostat. HVAC = emissions. Eat less beef. Corn fed moo=methane. Buy shit with a buy it for life mentality. Get involved with your local urban planning and zoning. Everyone can do all of that right now.
Down the road, vote for the most climate friendly candidates. Run for office if you can.
Get solar panels so you can run your AC guilt free when the sun is shining.
Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.
As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades:
How much each change to the atmosphere has warmed the world:
Recommended actions to cut greenhouse gas emissions in the near future:
Anti-science, inactivism, and unsupported conspiracy theories are not ok here.