How can I make it so that when I press C-xC-b to access the Buffer List that that buffer automatically takes focus instead of having to switch to it manually with C-xo? I can't find a variable that customizes this.
You can replace the command
list-buffers which is run with
C-x C-b to a function that does what you want. In this case
buffer-menu-other-window opens the buffers list in another window with focus. Adding the following snippet to your init file should remap
C-x C-b to the new function.
(define-key global-map [remap list-buffers] 'buffer-menu-other-window)
global-map represents the keymap where
C-x C-b is bound to a command,
list-buffers the original command and
buffer-menu-other-window the new command.