Researchers want to learn if calderasib given alone or with cetuximab can treat certain advanced solid tumors in people with the KRAS G12C mutation. The goals of this study are to learn: * How many people have the cancer respond (get smaller or go away) to calderasib alone or with cetuximab and how these responses compare * About the safety of calderasib alone or with cetuximab and if people tolerate the treatments.