You will find recipes for drip brewing coffee as varied as just about anything. I’ve seen some that suggest using one rounded tablespoon of grounds per cup to be brewed! Are you freaking kidding me?! That’s over 3/4 of a measuring cup of grounds for a 12-cup pot! That’s gonna make mud, not coffee.
But maybe you like it that strong, so go ahead.
My mother used 2 tablespoons of coffee to make a pot, it came out like weak tea, but that’s the way she liked it, so that’s what she did.
At work I measure my coffee by weight, I’ve found that 2.25 ounces of coffee makes a pretty good 12-cup pot. At home I have a burr grinder on a timer, it took about a week to dial it in, but it now consistently makes a really good brew.
My point is that only you will know how much coffee to use in your particular coffee maker, experiment until you find what works for your palette and then stick with it.
That being said, always start with fresh, cold water (filtered it possible), grind your beans right before you brew and drink it when it’s fresh.