A Research Study to Compare Different Versions of Injectable CagriSema and Placebo in People With Excess Body Weight

Inclusion Criteria: * Male or female (sex at birth) * Age 18 years or above at the time of signing the informing consent. * Body Mass Index (BMI) is greater than or equal to (\>= ) 30.0 kilograms per square metre (kg/m\^2) or BMI \>= 27.0 kg/m\^2 with the presence of at least one obesity-related complication including, but not limited to, hypertension, dyslipidaemia, obstructive sleep apnoea or cardiovascular disease. Exclusion Criteria: * Glycosylated haemoglobin (HbA1c) \>= 6.5 % (48 millimoles per mole \[mmol/mol\]) as measured by the central laboratory at screening. * History of type 1 or type 2 diabetes. * Previous exposure to CagriSema in a clinical study.