Will not shift into drive from park

My friend gave me this car it would not go into drive. It would go into first, second then I could put it in drive. I checked the transmission fluid and it was really high (way above the high temperature lines and bubbly brown and I know I have not been putting any extra fluid in. Foamy dipstick too high to read. There is no check engine lite. If you put it in D from P then the engine just revs like it is in neutral. If you put it in first, then second, then it will go into D and I drove it a around the block, but I am scared to take it on the highway. I will work with it more tomorrow. I know it probably needs a transmission flush and filter ($350.00). Maybe there is a leak that is making the dipstick read wrong or something (high and foamy when no fluid has been added). I would like to get this thing running to take to work