You don't report anything. Your employer has already deducted the cafeteria plan and medical insurance premiums from the wages shown in box 1 of your W-2. There is nothing that you have to do about it.
Technically the medical insurance premiums are probably part of the cafeteria plan. Your employer might choose to show the amount separately for your information.
Cafeteria plan contributions and medical insurance premiums are not shown a W-2. Your employer might choose to show them in box 14, usually with the notation SEC125, but that is just for your information and has no effect on your taxes. Some W-2s have a statement attached or included that shows cafeteria plan contributions, medical insurance premiums, and other information, but that is not part of the actual W-2.