The study is testing a new study medicine to treat people living with overweight or obesity. The aim of this study is to see if the medicine is safe, how it works in your body, and what your body does to the study medicine. Participants will either get the study medicine or placebo (a "dummy medicine" similar to the study medicine but without active ingredients) given as an injection under your skin. Which treatment the participants get is decided by chance. The study medicine is a potential new medicine which cannot be prescribed by doctors.