Dad has a sore red eye with a pimple-like white bump on the white of his eye. what could this be? how could it be treated?

Pinguecula: This is a normal structure which the eye makes to defend itself against dust and wind. It is present next to the cornea (the front window) medially and laterally in the open space.It is more prominent during red eye conditions because it has few vessels, and so gets highlighted when the rest of the eye is red as it is paler. It does not need treatment.

Pingueculum: Your dad probably has a pingueculum caused by excessive exposure to sun and wind, i would recommend sunglasses and artificial tears. If there is no improvement or increasing pain, see as eyecare professional.

To make sure= exam: It can be several things and an exam will help to differentiate the lesion from a benign nature to a more concerning and potentially malignant nature. "a picture is worth a thousand words", and élan exam by an eye md is very important.