Do you mean true cedar (Cedrus.. libani, for instance), or Thuja, the kind that's planted on everyone's front lawn everywhere on the continent? They're very different, but both make decent bonsai if you know what you're doing.

I talking about true cedar like red cedar or white cedar

I've seen a few very nice Eastern Red Cedar bonsai. They're a bit rough & wild, but sometimes that translates into a great bonsai.

Red cedar is a juniper (Juniperus) and white cedar is of the Thuja genus (aka arborvitae). As noted, plants of the genus 'Cedrus' are true cedars.

Al