Keyboard Character Typing in Catalina 10.15.6 update

I updated to the latest software of macOS Catalina 10.15.6 but after that keyboard started to behave weirdly . I have a imac on the magic keyboard whenever i start typing it does something else like for example if i am pressing navigation keys its opens launchpad and whenever i type a sentence somekeys don't respond until its press 3 to 4 times but every time i press sound comes on keypress but it doesn't showup. i tried all troubleshooting methods of removing bluetooth devices, reseting bluetooth device and reset bluetooth module as well but nothing worked. i hope its a software glitch in the latest macOS if you find any other ways please help