The curvy, organic shapes was created in Illustrator and inspired by Veerle’s blog, which, sadly, seems to have disappeared and her tutorial along with it.
See my post: https://greenbee.blog/2019/09/20/make-a-segmented-curvy-wave-in-illustrator/ on how to create a segmented curvy wave. There’s my tutorial on how to create a basic segment and the rest is pretty easy to figure out.
Three Bees in My Bonnet 