That's obvious but how do you put it on a grid in a practical way? I figured it out now myself. I auto-tile the top tiles and then place the rest manually.
I really like your asset pack, it is extremely good. For one, sprites are generally well done artistically. Also tiling is efficient and smart (much to learn for me).
I hope you do more of these. Maybe different biomes, caves, etc. By the way, your Discord link is broken.
I think the water tiles have some inconsistencies or bugs. I would like to report these.