Double Comment Buttons & Image Hover Problem

Sorry if this is hard to understand, new to this. First, when I hover over my featured image for my posts that link into my post, the whole screen becomes larger and scrollable vertically. My layout fits inside a web page naturally, but when I hover it becomes way wider. There’s also this chainlink image that appears on the side when I scroll way outwards and nothing else. This happens on my home page and category page, any page that provides a link to my full post. I have only one social media plug-in so far, so it can’t be that (I think). I’m not sure if it’s the theme or not. I want to have a featured image on ever blog post and this hover thing is really annoying already. I already tested different size images as a feature as I was thinking the image was too big, but even small pictures (300 x 300) still cause the hover and expand effect.
I am using the ‘No Nonsense’ theme.
Also, each actual blog post there is a double of each comment, person and clock icons. These don’t appear on the shorter home version of the posts.

Scrollable horizontally.