WordPress plugins are great (and necessary) for extending the functionality of a site. However, it is very important to make sure the plugins added are safe and functional. The most important safeguard is to source the plugins from a trusted website, like WordPress.org or the hosting platform being used (in this case, IONOS). There are other indicators one can use as well, such as number of active installations, when the plugin was last updated, and whether or not the plugin has been tested for compatibility with the version of WordPress being used. There also exist plugins that can scan plugins for vulnerabilities.
For my custom plugin, I chose to use WPCode. This plugin allows admins to insert snippets of code into the site pages without having to edit the site code directly. This is useful for installing widgets, such as UserWay’s Accessibility Widget.