The molding piece that is on all of the door's is coming off. How do I replace it and what type of paint do I uses for it?

 

If it's just coming off but still looks good then stick it back on. You may need a heatgun or hairdryer to get it off the rest of the way and to get the old tape off. Then just get some 3m double sided tape (it is kind of like foam or something...not like normal tape) and autozone etc and put it on the molding then stick it back on the door.