Once someone who’s authorized to order a strike, e.g. Putin, gives the command (“presses the button”) - what else would Putin need to do for his command to be c

Once someone who’s authorized to order a strike, e.g. Putin, gives the command (“presses the button”) - what else would Putin need to do for his command to be carried out? My guess would be he doesn’t need to do much, and that the “risk” would be someone down the chain of command refuses to carry out the order.