This is just one day a week you have to go in- is that correct? There is nothing wrong with making your discomfort known to your supervisor. Maybe expressing that will bring about some suggestions by them. Maybe put you on an end cubicle or maybe there is enough space to have a space between you and others - an empty cube or two.
Keep sanitizing often. Avoid as much group stuff as possible - during breaks go outside if possible - even eat lunch in your car to give you mask and mental breaks