In this very hot weather yes drink water but also do not neglect salt or electrolytes.
The Romans knew soldiers could not march for miles or fight without salt. The Ancient Roman practice was to pay their soldiers a salārium or wage with which to buy salt. Salt enables the body to retain water - which is quite valuable in hot temperatures.
Too little salt is a thing. Hyponatraemia can be caused by over hydrating without balancing with salt or electrolytes. People occasionally die of this in endurance events when they over hydrate at the expense of salts.
So make sure to pay yourself the right salary these hot days