Avada Fusion Wordpress content hosting area

I have been building a new wordpress website staycancerpositive.com.

I am selling an online book/ program. if someone was to buy this form me, I want the site to allow there username and password to this program. I would like this program hosted on the site but hidden unless the user has paid.

I would also like some scrutiny features so the content cant be exposed.

I would like the content to be hosed in an online book format.

I would also like the cones to be counting towards my SEO on the site

I would like this doing ASAP

Jake