A Study to See How Metabolism is Influenced by Weight Loss Due to Intervention With Cagrilintide and Semaglutide Compared to Diet

Inclusion criteria: * Male or female (sex assigned at birth). * Age 18-65 years (both inclusive) at the time of signing the informed consent. * Body Mass Index (BMI) greater than or equal to (≥) 30.0 kilograms per square meter (kg/m\^2) at screening (Visit 1). Excess body weight should be due to excess adipose tissue, as judged by the investigator. Exclusion criteria: * Female who is pregnant, breast-feeding or intends to become pregnant or is of childbearing potential and not using highly effective contraceptive method. * History of diabetes mellitus of any type, other than gestational diabetes mellitus. * Claustrophobia or severe discomfort of being confined in small rooms. * Contraindication for magnetic resonance imaging (MRI) scanning as per local guidance, including physical limitations that prevent the MRI scan. * Unusual meal habits (including, but not limited to, eating disorders) and special diet requirements or unwillingness to eat the food provided in the study. * Treatment with metformin or other glucose-lowering agent(s) within 90 days before screening (V1), regardless of indication. * Treatment with any medication prescribed for the indication of obesity or weight management within 90 days before screening (Visit 1). * Presence or history of malignant neoplasms or in situ carcinomas (other than basal or squamous cell skin cancer, low-risk prostate cancer, or in situ carcinomas of the cervix or carcinoma in situ/high grade prostatic intraepithelial neoplasia) within 5 years before screening (Visit 1). * Physical measurement exceeding the dimensions or load capacity of the magnetic resonance imaging (MRI)/dual-energy X-ray absorptiometry (DEXA) scanner.