Can I use existing wired sensors with IQ Pro?

Looking at the pictures you provided, those wired devices, aside from the keypad, can be used with an IQ Pro.

You can also use something like the IQ Panel 4 along with an IQ Hardwire PowerG, which converts them into a wireless signal that the panel can receive.

The IQ Pro and IQ Hardwire PowerG both have a siren terminal, so you can use the siren that was installed as well.

Steps for getting started with an IQ Pro can be found here:

Steps for getting started with the IQ Panel 4 and IQ Hardwire PowerG can be found here: