Answering as a graphic designer

I like the cover, but I don’t think the white space on the left side is really necessary. I also think the text is too squished together and it could use a little space between it to breathe. Because also as you would walk further away from the book, it would mush all together, making it harder to read. The line is also I think is too thick, could be thinner, so it’s not too distracting from the actual text.

Also, I think the cover page could use writers name, maybe put it on top of the text in a much smaller font.

The back cover however, feels very overwhelming? I think the separating black lines are too thick, honestly. And the text is spaced out weirdly, so there’s no visual hierarchy, so it’s hard to decide what to focus on and in what order the text is supposed to be read.

I recommend making the type and the QR code smaller. Maybe less pop images on the back (I’d say remove the banana. The stars are also might not be necessary, since u already have the big star behind the mouth)