It depends— do you go in to work everyday? Have a special occasion? Is your mental health positively effected by showering at least to some complicity? If you don’t want a full shower, wash or bathe your body. Dry shampoo your hair. Brush it thinking about how good it feels.
Every night to not only wash away the day’s sweat and dirt, but also stress and to put you in a relaxed in preparation for bedtime.
How often to shower is all mainly preference. Several times a week is a good standard. Daily showers can dry out the skin but a lot of people love a daily shower. What makes you feel best while still staying hygenic is the only true answer.
The best option is once or twice a day. But once every other day is fine too if you don't sweat a lot and do morning and night time skin care routine religiously.