I'm looking to implement a forum page on to my already established website but having difficulty adding it via Elementor. How is this accomplished? Would it need to be a block added to the page or since I'm already using a theme, would it not apply?
You don't need Elementor for the forum page. Your forum page should already be created and it should be available if you call the /community/ slug with your domain.
If it's not there, then don't use Elementor Blocks. The [wpforo] shortcode should be inserted in a simple classic text editor box as a regular text (don't use shortcode boxes) in dashboard, not on the frontend.