Hah, I like your username! Welcome to the forum!
Coming from raster graphics, you'll have to learn a different way of thinking about how to draw an image. Personally, I was overjoyed to find vector graphics, since I found raster graphics so very hard to use.
As we find with Inkscape, there is often more than one way to go about it. I just notice that some of the "boxes" are different sizes. For that, I would use a different approach. I'd try something like this. I'll make a video too
Note that some of this is using intermediate skills, and the video doesn't tell you which key shortcuts I'm using. Maybe I'll list some of them and maybe you can sort it out?
To draw a circle, or scale (re-size) a circle, always hold the Ctrl key (or else the circle will be lopsided). Shift + Ctrl + drag, to resize the circle from the center.
To select more than one object, one at a time, hold the Shift key while you click on each object.
To select more than one object, all at once, drag a selection box around them with the Selection tool.
I was using the 1 key to set the zoom to 100%, and the 2 key to set it for 50%. But I think you'll need to zoom out even further, to make the circles large enough. In my video, the circles are still too small, I think.
When something which was selected suddenly disappears, I was using the Delete key.
Oh, I just realized, I forgot to show you the Snap control bar. I would have circled the mouse around it. But just look at the right edge of my window, in the video, and set up your snap settings just like mine (the light colored ones are enabled, sorry for the weird theme color).
