The Version tab is where you can deploy your plugin and push updates, bug fixes and other improvements.
A plugin can be published on an open source license (MIT) or a private license. The open source license will make the plugin free on the plugins marketplace and other users may copy the code. Note that once a plugin has been published as Open Source, you won't be able to take it back to private.
When a plugin version is set to private, you can authorize some apps to have access to this plugin. Note that this is a different concept from the test application you use to test your plugin. These apps will be able to use the plugin in production.
When you clone an app that has access to a private plugin, Bubble does not remove the plugin from the newly created app to prevent the app from breaking. If you want to withdraw the plugin from the copy of the original app, you should delete it in the Plugins Tab of the app.
When you deploy your plugin, or push a change, you can define the change type and define a caption for the deployment. Deploying will generate a version number and will prompt users that have installed your plugin to upgrade their plugin in their app.
Congratulations on getting your plugin out there! Whether you are offering it to the community for free or monetizing it, it's a huge accomplishment and helps strengthen the Bubble ecosystem.
After your plugin is live, you may want to keep an eye on any feedback or ratings from users. You may also start getting bug reports from users directly. As a publisher of a public tool, it's important for you to communicate with your users and to set expectations about future development (or lack thereof) as appropriate.
Once your plugin is approved and live, it will show up in the marketplace for other Bubble users to buy / install. You have the ability to change your plugin's marketplace listing or publish a new version of the plugin whenever.
Each plugin's listing generally shows the number of apps a plugin is installed on. Note that this does not necessarily correspond to the number of users who have purchased your plugin, if it is a paid plugin. The number can diverge because of a number of reasons where users have the plugin installed on their app but they are not paying for it, e.g. because they used a template that has the plugin, because they copied an app that has the plugin, because they downgraded their plan, etc. Rest assured though that if your plugin is a paid plugin, a user can only use it if they have paid / are paying for it (i.e. having it installed does not automatically let them use the plugin).