Bootstrap Studio is a unique type of program. While it is based on a “drag-and-drop” approach, it actually kind of requires that the user have a basic understanding of website structure (and Bootstrap website structure in particular.) The documentation isn’t bad, but it doesn’t really provide a step-by-step walk-through for putting together even a basic website (like you’re describing.)
Although it is marketed as website builder for beginners, it really is geared more towards someone who has a basic understanding of how websites are built, and has some familiarity with the the DOM (page structure, style and content), as well as HTML, and CSS. It’s not as intuitive or (and please forgive the phrase) “idiot-proof” as platforms like Wix, Weebly, Squarespace or GoDaddy Website Builder. Those programs constrain the user so that it’s difficult to do things wrong, but it’s also difficult to customize things how you like. In comparison, Bootstrap Studio allows you much more freedom to design things your way, but the downside is that it’s also easy to build websites… incorrectly.
When I first started using this program, I already had some experience building websites using a static (non-responsive) website builder, and had taught myself the basics of HTML and CSS, so the program made more sense to me than to a total beginner who has never written a line of code.
Nevertheless, there was still a learning curve, and what I found helped me the most was watching their instructional videos and actually building one of the sample websites in one of the videos (I think it was the Tesla website) in real-time, as I watched. I’d just stop and start the video, and follow along with the program. Doing this just one time instantly gave me a much better understanding of how to use the program, and construct a website from scratch.
You can find all their videos here. The older videos were made using older versions of the program, so the user interface looks different, but the fundamentals of the program are all still the same. I would watch all the “how to” videos, and try building one of the sample websites. This should give you a lot more insight into how to use the program.
Additionally, it may help to read the actual Bootstrap documentation so you can understand the Bootstrap layout/grid system, which is basically something like… section > container > row > column > (content). So you start with a Section, drag it into the Body, then drag a container into the section, a row into the container, and then add columns to the row as needed, and place your content (text, images, etc) inside the columns.
Lastly, take a look at the various Bootstrap Tutorials and examples on W3 Schools. They will show you different examples of how components are combined to create page layouts.