Finishing touches needed to website. Backend & tidy up work.

I have a website that is Wordpress, I made it myself (I'm not a web developer) and i'ts online but I need help with some of the backend things.
Please contact me direct for the site url. it's an adult site with fetish content, 18 + so please only contact me if you are comfortable working with an adult site that has rude content.

It's a basic 5 page site, no members area.

Things that I know need finishing-
Get the site registering with search engines, I tried and failed.
Improve page description/page title along with tiding up my coding as I just tried my best and fix heading structure.
Build backlinks and CDN if needed and add site disclaimer to warn user there is adult content..
Paypal payment button needs centred, its currently on the right side of the page.
Facebook/twitter/email links open up the new page in the browser and close the session, needs altered so it opens a new page.

Restrict access to my pages such as /index.php - fontawesome-webfont.woff2 - /wp-json/oembed/1.0/embed as I am seeing on my statistics that people are using these pages and I don't want them too.

Other work is available. I have another site that needs migrating onto a new server and updating.