Here is a list I have formed:
-Switch to Esim
-Build more apartments
-Use shampoo/conditioner bars
-Put carbon labels on products
-Buy stuff at the store
-Eat plant based
-Prioritize transit over cars
-Switch to Ecosia
-Recycle
-Give homemade gifts
-Compost
-Be organized
-Avoid synthetic cloths
-Switch to green burials
-Buy reputable carbon credits
-Mandate microfibre filters for washing machines
-Install Linux on old computers
-Switch to Electric car -Shut down all oil operations
-Pickup litter
-Ride your bicycle instead of the car
-Adopt kids and companions instead
-Build more green spaces
-Convert animal agriculture land to wild lands
-Support repairability
-Ban private jets
Using windows is also massively wasteful, it spends probably more than half of the processor usage on analytics and tracking stuff. Linux or other free kernels are much better in terms of power usage, on old and new hardware
I notice my resource usage dropped to half after switching.
The Linux kernel was supporting hardware that was 30 years old.