It's not the amount of drink per se because many food stuffs break down as fluids. The thing to look at is the colour of your pee.
First of the day - i.e. after 4.30 a.m. - will be dark. The rest urine passed should be straw coloured and non smelly. Any lighter and you are drinking too much which can be dangerous, if urine in the day remain dark then you are not hydrated enough.
It was the bottled water companies that suggested 2 litres per day
which can be too much. I start the day with blackT and 2 sugars; the same mid-morning. Probably 2 more during the afternoon but I find that tea alters flavour during the day
. I have bottled water if I'm thirsty and take my evening meds with chocolate milk shake, home made. No idea about how much each drink measures. My pee remains straw coloured ……..
I found that if I didn't drink enough in the day I would be up more in the night as the kidneys have to work harder.