"To have a drink" means to consume a beverage, usually referring to an alcoholic beverage, but it can also include non-alcoholic drinks like water, soda, or juice. Full definition
You aren't having drinks with a female friend, you're spending time with a potential love match, and sharing too much too soon can cause them to run for the hills. (welovedates.com)
Just to add some actual evidence to the cold water discussion, I studied how much water cats would drink at different temperatures using special night vision cameras. (pethelpful.com)
From having a drink in the evening to sweating out a long session at the gym, they have their own preferred methods of getting to sleep and adjusting to a new time zone. (policygenius.com)