Accidentally pressed unknown keys using USB PC keyboard with iMac now keyboard and mouse don’t work.

Using a PC keyboard trying to enter $ I accidentally pressed shift + unknown FN key now usb keyboard and mouse do not work. since the usb keyboard And mouse are not working I tried retracing my steps using my apple wirless keyboard and mouse which made things worse. Now the apple wireless mouse selects all text from the beginning and will not deselect. No idea what I pressed either time now.

as far as the usb keyboard and mouse not working I checked the USB ports which are functional. The wireless keyboard works and mouse other than the selecting issue... any suggestions on restoring the usb devices and fixing the selection feature?

thanks,

andrew

update: just noticed the icon bar at the top of the display now has a icon that looks like a hub or mound, domed with a circle in the middle and two arched WiFi signals off the top. When I click to quit all options are greyed out.