Filmora subscription and Effects & Plug-ins subscription are two different subscription plans that need to be purchased separately.
Filmora subscription is for the program itself, which means you could use the license to edit the project and export it without watermarks.
However, Filmora has some premium features and resources that need to be paid for separately, such as adding additional effects and resources (title/audio/music/transitions, etc.) to your projects. That is what the Effects & Plug-ins subscription includes.
If you have purchased the full Effects & Plug-ins subscription, then you can download and use corresponding paid resources.