You'll have a greater impact if you quit driving. But you can't cheat and take public transportation, if available. You either have to walk or use a bicycle or not go anywhere. Since I've retired, my going places has been reduced, almost to the point of not going anywhere. That means no nude hiking in the national forest, unfortunately.
My next door neighbors when I was little, in the 1950s, would laugh at our petty attempts to save the world. They lived in a four-room house, never had a car and walked everywhere. They kept a big garden and even raised two children. Of course, "downtown" was only three or four blocks away and everything you might have wanted or needed was there, within easy walking distance. That was when a small town was much more city-like than anything is today. But that was then. It isn't like that now. There are no businesses on that four block stretch of street that were there then. Now, a car is virtually a necessity.
My folks also walked most places, too, as far as possible, although, ironically, my father was a truck driver. My grandfather walked to work (at the railroad shops). He walked home from work in the rain one day, caught pneumonia and died at the age of 67. He may have put off retiring because of the war.