Here it is!
-Art-
Got to say you have some amazing art. The sketch like line work is really good and the color give a pencil and pastel like quality making it rather unique. It also ties in well with the time period the series seem to take place in. Your proportion are on point and you really give us a nice look of the town using it in a great way for transition scenes.
I normal I leave font talk for the writing part, but I am doing it in art cause it fits more here. I know you selected one for easy reading, but it being so clean and modern clashes a bit with the art style. I think a font like https://www.1001fonts.com/im-fell-english-font.html might suit better. Is still easy to read, but adds a bit of imperfection (scribble like) that goes well with the sketch like art. This is a personal opinion of course, just always feel font are really important to go along with the art.
Is just for the text in speech bubble, the one use for effect fit perfectly.
Outside of the font your art is on point, the style is unique in itself, animal, town and people are all done in a great way and you have really good face expressions. As for the storybook, I do believe you nail that feeling with the art. The art doesn't give it a comic like feel even though is format like that, it feel like pages you normally go throw when reading a drawn storybook.
-Writing-
I like that you use different speech pattern on character and give 'accent' to some, make it feel like a more natural speech. I like the amount of text use, it make it easy to read and follow! The prologue is perfect in that it gives a bit of info but leave a ton of mystery and intrigue to keep one hook instead of being an info dump.
I also couldn't find find any typo or error from my reading.
-Paneling-
I can tell you plan for the vertical format from the start and achieve a great method. The panel all flow nicely and you put them in good position moving down guiding the eyes where to go which is important. Great use of black also for clearly tense moment (the crack forming and guy having the scare of his life). Keep up this vertical comic method as is working really well.
-Story-
You just started so not much I can see here, but I'll say you have a nice start in peaking one curiosity on the kid on the tree and what it means so as far as hook goes for the start of a story you did a great job!
Hope this help and you have a really good comic with amazing art!