If you don’t see ACF in the list of plugins this generally means that ACF is installed as part of the plugin. Look in your theme to see if it is there. If it is then you will not be able to update ACF using the plugin updater on the plugins pages….
You will need to install in normally. Installing ACF normally will override the version in the theme as long as the theme author did it correctly.
As far as not seeing it in the admin menu check this https://www.advancedcustomfields.com/resources/how-to-hide-acf-menu-from-clients/
