Small software showing the camera on screen:
camdesk-1.2.1.zip

Small software showing the keystrokes and the mouse clicks on screen:
showmouseclick.zip
showoff.zip

Screen recording sofware for windows:
Daniele had a link to “ScreenRec_webinstall_all.exe” here that I can't upload it because it is a .exe-file I recommend
https://linuxecke.volkoh.de/vokoscreen/vokoscreen.html
or
https://obsproject.com/