Hello,

1. To make it responsive, you need to edit it via the page builder. So first go to Elementor -> Settings -> enable the posts type here – https://take.ms/J8gsS, then edit the single post page via Elementor.

2. Use the code below to remove that info:

.single-post .wd-entry-meta {
    display: none;
}

Paste it into the “Global Custom CSS” area in Theme Settings -> Custom CSS.

Kind Regards