Anything promising fat loss should be ignored. Caffeine and other stimulants give a short lift but give little fat reduction or energy. Weight loss is sustainable with diet and exercise, not drugs.
Another supplement I'd avoid? Preworkout. Preworkout usually means caffeine or another stimulant. Getting nervous, high heart rate, and blood pressure can be harmful.
Detox pills waste money too. The liver, kidneys, and GI tract detoxify your body naturally. Detoxing doesn't require supplements.
Avoid collagen supplements too. Collagen supplements may not assist your skin, joints, or hair because digestion breaks it down. The same amino acids are in protein-rich foods.
BCAAs are also avoided. BCAAs, popular in fitness, are unnecessary if you get enough protein from complete foods or a good supplement.
Avoid testosterone supplements. Over-the-counter "test boosters" usually include ineffective herbs. Medical treatment (such TRT) is better for low testosterone.
You're wrong about vitamin C for colds. Vitamin C is vital, but excessive dosages won't prevent or lessen colds in most people. Fruits and veggies are sufficient.