It’s someone who designs infrastructure, so roads, buildings, bridges, sewer systems, etc. Basically if you think about anything a construction worker builds, a civil engineer/team of engineers designed it. There are different categories of civil engineers. Structural engineers make sure a building can handle the weight of everything on/in it. Transportation engineers design highways. I’m a geotechnical engineer, so I deal with soils (dirt) and make sure the ground can support whatever is being built.
Stop buying what shit? Everything? Corporations lobby for policies that save them money at the cost of our environment. Yes there are things individual people can do to help but posts like this one from CNN shift the focus from the actual problem