To install or upgrade H5P content types and libraries, log in as administrator and from your Administration dashboard visit System settings Integrations and then the tab H5P (1). This will get you to the H5P settings panel.
To install new or update existing H5P libraries click on the corresponding link (2). This will get you to a tabular list of all available H5P libraries and content types in your system, along with details about them.
Notice the Install (3) and Update (4) buttons on the top left corner of the page and use the respectively to install new H5P content types or upgrade existing ones.