You can install some external plugins to Talend Studio via the Install wizard, which can be opened from the menu.
The external plugin you want to install must be compatible with Eclipse 4.20, based on which Talend Studio is developed.
By default, the external plugin that you have installed is activated for all your projects.
To uninstall an external plugin, click already installed in the Install wizard, and in the pop-up Talend Studio Installation Details wizard, select the items you want to uninstall and click Uninstall....
For more information about installing and uninstalling an external plugin, see the official Eclipse documentation Updating and installing software.