WPBakery Page Builder premium plugin is included in the theme package free of cost, so you do not need to activate the license for this plugin however you will be able to use all the features of plugin without any issues. So please ignore the notice of license activation as you have the rights to use it without license activation because this plugin is bundled in the theme itself.
But still if you want to activate the license then you can purchase plugin separately and activate it using the purchase code of that specific plugin purchase.
We regularly update our theme with changes, feature additions and full testing of premium plugin updates for proper compatibility with theme. So we recommend you update the theme and included plugins instead of directly updating the plugins individually to avoid any compatibility issues.
Note:WPBakery Page Builder plugin do not allow to use their own default template libraries in theme bundled plugin version, if you want to use their default templates then you will need to purchase the plugin separately and activate the license to unlock their library.