Yes, it will. https://support.microsoft.com/help/15090/windows-7-install-service-pack-1-sp1 tells about updating to SP1 if you have the original version. I would recommend to download it yourself in stead of using Windows update for that.
And if you have SP1, download the convenience rollup from https://support.microsoft.com/nl-nl/help/3125574/convenience-rollup-update-for-windows-7-sp1-and-windows-server-2008-r2 .
hey everyone, I would like to know if I use the installation cd to put my laptop back to windows 7 will; under windows update still find the updates needed for the version of windows?