I would like to post plugin and have questions

Wordpress plugin. It is a widget related to outer independent service. That service have a subscription premium model and a initial free service.
Can I, as author of such a plugin to set a price for a plugin and this price will be separate to core service pricing model. So, when a Wordpress user will install this widget-plugin, they may use both free/premium service of related service? Can the plugin includes information of free/paid related service inside it? In common this is a question of ability to separate price to plugin and a price of service itself to which the plugin is related to.