I have read the first volume (and then stopped because I hope for it to be selected for the Absolute Beginner’s Book Club, though I do have the second volume, and absolutely intend to continue at some point!).
I found it incredibly easy to read. The only things that were a bit difficult are some of the in-between chapter stuff because they can be handwritten, which makes it a little more difficult. Generally speaking, the manga will be even easier than the anime, imo, though, because you can take your time instead of being beholden to their speaking pace.
If you want a little more detail on my thoughts on the manga, you can refer to the nomination post in the ABBC I posted for it!