AddThis plugin-add on

Hi, I signed up for an account with AddThis and was given the html code post on pages. It states to place on page html code just above body.

I went through the Editor and all the pages and could not find a place to post/paste the code.
When I look at the Theme and the Child theme,there’s no home page html showing up to place the code. Am I missing something, or do I need to go to the cpanel to paste this code. I would like the adthis to show up on all the listings or the listing page.

second issue,

My blog blocks on the home page are not even, is there a way to get them to line up on the home page

does anyone know how to setup the “login with LINKED social button on the registration page.

My website is http://www.riachannel.solutions
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