the usual configuration of a .inputrc is given for a PC keyboard.

the safest method for you is to edit your ~/.inputrc with vi(m). go to insert mode,

type "

type Ctrl-v

type PgUp (->a strange string is displayed),

type the following string ": history-search-backward

Do the same on another line for PgDn (replace backward with forward).

Save. Relaunch a Bash session. And that's it.