Replace your car with an electric one! (even though it still works fine and will end up in landfill, never mind the environmental cost of producing the new one, or the source of the electricity it uses)

A new EV breaks even with a used car in less than a decade. It does not matter if it is getting its energy from coal, it still will emit less carbon within a decade.

Recycle! (even though 90% of it ends up in landfill anyway because we don't want to pay to actually recycle it)

90% of plastic recycling. That is thanks to the oil companies who saw backlash against the ridiculous amount of plastic in the 70s and decided to invent a resin code whose symbol mimicked the recycling symbol. Recycling centers were flooded with a ton of plastic which they did not have infrastructure to actually recycle. China took it for a couple decades and then it became unprofitable for them. Basically only resin codes 1 and 2 are recyclable. But most people think all of it is. Absolutely recycle metals. If your city has recycling pickup and you are not recycling stuff like aluminum, you kind of suck.