apt update doesn't update your packages. It updates the repolist to get information about new packages or versions of packages. apt upgrade is what actually updates your packages to the newest version. So you need to do BOTH apt update AND apt upgrade to update your packages.
Hi .. I'm using kubuntu 20.04.. .my laptop mouse double tap not working in kubuntu os... please give me a solution..if any seperate software available for use the double tap function.??