Touches claviers

Why can’t i change my fonction on my clavier microsoft
I try ALT CTR + 1 or 2 or 3 and i charge CRT 1 2 or 3 and nothing is relesed on FLIGHT
I try also alt CRT + one touc '1, 2,3 or another and i have no result fontionnal when i use one on this touch
Somebody can help me please ? I Thank the communauty for one answer on this question

Excuse my englih it is very bad ,but I think that you can understand what i would say