The purpose of this study is to compare the relative bioavailability of JNJ-64565111 between subcutaneous (SC) administrations in the upper arm versus the abdomen, and between SC administrations in the thigh versus the abdomen in otherwise healthy overweight/obese participants (Part A) and to assess the gastrointestinal tolerability of JNJ-64565111 following a dose titration in otherwise healthy obese participants at 6 weeks (Part B).

Inclusion Criteria:

Part A and Part B:

- If a woman, must be postmenopausal (no spontaneous menses for at least 2 years), surgically sterile, abstinent, or, if sexually active, be practicing an effective method of birth control before entry, throughout the study and for at least 30 days after the last dose of study drug

Part A:

• If a woman, must have a negative serum beta human chorionic gonadotropin (hCG) pregnancy test at screening; and a negative serum pregnancy test on Day -1 of each treatment period
• Body mass index (weight [kilogram {kg}]/height^2 [meter {m}^2]) between 25-40 kg/m^2 (inclusive), and body weight not less than 75 kg

Part B:

• A woman must have a negative serum beta-hCG pregnancy test at screening, on Day 1, and before each SC injection, except on Day 8(+1). On Day 8(+1), women must have a negative serum or urine pregnancy test depending on the test performed at the investigator's discretion
• Body mass index (weight [kg]/height^2 [m]^2) between 30-50 kg/m^2 (inclusive), and body weight not less than 75 kg

Exclusion Criteria:

Part A and Part B:

• History of or current clinically significant medical illness including (but not limited to) cardiac arrhythmias or other cardiac disease, hematologic disease, coagulation disorders (including any abnormal bleeding or blood dyscrasias), lipid abnormalities (that is [ie], fasting triglycerides greater than or equal to (>=)500 milligram per deciliter (mg/dL) and/or total cholesterol >=300 mg/dL), significant pulmonary disease, including bronchospastic respiratory disease, diabetes mellitus, hepatic or renal insufficiency, thyroid disease, neurologic or psychiatric disease, infection, or any other illness that the investigator considers should exclude the participant or that could interfere with the interpretation of the study results
• Clinically significant abnormal physical examination, vital signs, or 12 lead electrocardiogram (ECG) at screening or at admission to the study center as deemed appropriate by the investigator
• Clinically significant abnormal values for hematology, clinical chemistry, or urinalysis at screening or at admission to the study center as deemed appropriate by the investigator. Participants with serum sodium less than (<)130 milliequivalents per liter (mEq/L) at screening should be excluded
• Known allergy to the study drug or any of the excipients of the formulation
• Donated blood or blood products or had substantial loss of blood (more than 500 milliliters [mL]) within 3 months before the first administration of study drug or intention to donate blood or blood products during the study or within 2 months after the completion of the study