the battery isn't charging

my friend has a  2007 Jeep compass he asks me to replace the starter so I
did so. after installing the starter. I had to jump start but it started right. but
then the battery wasn't holding a charge. so I replaced the alternator and the
battery still wasn't holding a charge, so of course, I replaced the battery and
the battery and Terminal Clamps. still, the battery dash light stays on and the
battery isn't charging. I checked. I was told to check the fusible links the but
is only one wire that is connected to the positive cable and it goes to the fuse
box. if I pull the fuse that the wire connects to it won't even turn over. when I
replace the fuse it starts up. so I assume the fusible link is good because if it
wasn't the car wouldn't start. I don't know what else to do after replacing the
starter the alternator, the battery, and the Terminal Clamps. I'm at a dead
halt. I don't know why the battery isn't charging. I have replaced all of these
things hundreds of times and never had this problem. Can you please help
me before I lose my mind?