I have got an old car and it has what seems to be mold or chipped paint...what is it and how do I fix/clean the car (exterior)?

Looks like the clear coat is compromised, which can have various reasons. The only real fix is to re-paint the vehicle or at least the panels involved with the right type automotive clear coat. Most rigs since the mid-90s (and earlier) use multi-layer paint systems where there are primer coats, color coats then clear paint to provide the final seal and gloss effect. If you aren't familiar with painting then take it to a local budget shop and see what the cost is to just fix the problem and not do a total re-paint, THEN see what a total repaint will cost and see if the difference is worth paying, or if it's not worth dealing with at all. No, you can't polish it out or put waxes on top of the dulled areas to improve the look. 

I have a 2001 Chevrolet Cavalier that looks just like that. Guess Clear coat wasn't meant to last that long. Lol

That would be the disintegration of your clear coat. Not a whole lot you can do other than getting it repainted.