Adding Images to Widgets

I’ve been able to use the widgets such as “Content Middle Left Section” and “Content Top Section” to add headers and play with the layout. How, now, do I add images and, more importantly, content to each of those sections?

For example, the content that I wrote for the website’s home page shows up using another theme. After installing ColorMag, it doesn’t appear when I do a preview. The text can be seen in Dashboard>Pages>Home.

I have other questions, but I’m assuming you’d like me to keep it to one question per post? I appreciate any help you can provide. Here’s a link to what I’m working on: https://pc-assistants.net/.