ok i flooded the mines but still cant get into baldurs gate, why?

Get to bridge area, cross the bridge, talk to guard, talk to Scar, go to west.

did i have to be on some kind of quest first because i just went strait to mines, went in flooded them came out and what bridge area are you talking about and what gaurd and whose Scar?

All right, before you get any more confused...

Go to the Friendly Arm Inn map. Go north of the inn enclosure and take the north way out of the map. The destination selection screen should show you a new map, one that has a blue farm-looking icon. Choose it. Once you're done on this map, exit north to another new map. All the stuff Vedran is talking about is on that map.

(minor spoiler)

Might want to carry a couple antidotes with you.