I'm completely stuck.

I'm on Claire's run, first time playing a RE game. I have the lion and the unicorn medallion, I got the grenade launcher, the red jewel, the spade key, the wire cutters and the c4 explosive. I've been to every level possible except for the basement but I have no clue where the basement is. I need a crank for the crank handle spot, a jack for the bookcase in the library, and the USB drive for the STARS office. I've been all around the map, I literally cannot do anything with the stuff I have. Please help.