watering

So I'm calculating how much water will I use for entire grow. I have a soil moisture meter , but I don't have my soil yet.

How much water should I give a vegging plant thats living in a 2 gal pot, per one watering?

And how often do I water a flowering plant?

Well basic rule of thumb is to stick your finger in the soil up to your knuckle if its dry, water, try to get a feel for the weight when its dry, and when its wet, when you do water, water enough till some drains out of the bttm. (drainage will also depend on your soil mixture)then dont water again for days, remember you dont want your soil saturated all the time, for cannabis is a weed and you want your roots searching for that water,thats how you grow a healthy root system, right amounts of Oxygen and H2o

yeah I know all this but approximately I should know in liters how much a 2 gallon pot of soil will hold.

thanks for responding tho.