Okay, so my car had been leaking fluid for a.

Okay, so my car had been leaking fluid for a few weeks but me and my mom decided it most likely was just an oil leak and we would have a family member look at it soon. But now my brake warning light is on in the car. The car rides fine and the brakes seem to be working great too but I stopped driving it for now until we find out what is going on. The fluid is leaking from the front driver's side almost right behind the headlight. The fluid is a pink color, which I found out means it is transmission fluid. What kind of repairs should I expect? I'm hoping it won't be too much haha