Can not get the question mark to work

turn off your PC and check all the connection are OK

then restart the PC
start >> Run > Notepad
there you check all keys of your keyboard

In case any of the keys are not working you will come to know.
Secondly
meanwhile you can use the Alt code for typing
Alt 63 ?
Alt 123 {
Alt 125 }
Like that

all the best
like that