I have a 2006 Honda Civic I lost the master key. How can I program a key i bought if my alarm turns on?

I have a 2006 Honda Civic I lost the master key. How can I program a key i bought if my alarm turns on?

Call the dealer and ask them

You only buy keys at the dealer and then you'll need to have the car towed there so they can program the keys to the vehicle. I won't even mess with a key purchased on line!