Is there any wireless keyboard-mouse combo, which will not waste an usb port of my laptop?

Solution
If your Laptop has integrated Bluetooth, then yes. If not, the peripherals will not communicate with the PC unless using USB.
You could get a USB hub which will give you more ports.
If your Laptop has integrated Bluetooth, then yes. If not, the peripherals will not communicate with the PC unless using USB.
You could get a USB hub which will give you more ports.
 
Solution
Which version of windows are you running? If it is Windows 8.1 or 10 (on the latest version) then it should run both a bluetooth keyboard and mouse.