There's something on my neck. I don't know what it is. Help me have a look
This kind of thing on the neck may be caused by allergy or inflammation. You can consider applying some anti allergy ointment for treatment. Usually, you should pay attention to the light diet and don't eat seafood and other heavy flavor foods.
If there are some red marks on the neck, it may be the symptoms caused by excessive extrusion. If there are some clinical symptoms, you can use some erythromycin ointment and other related drugs. If there are no symptoms, you can pay attention to observation.
According to your description and further combined with the two photos you sent, the skin surface of the neck is rough and unsmooth. Do you feel pain symptoms or itching symptoms, which may be a problem of tinea pedis. It is recommended to go to a regular hospital and register the dermatology clinic for on-site inspection, test the skin scraps, see if there is a problem of fungal infection and find out the cause.