I use another tilemap editor named LDtk and I managed to get it working properly with my tiles, but I came to know Tiled since years ago but I never understood how to use it with that terrain brush.
OBS: yes I watched lot of Tiled tutorials on youtube, but they only use tilesets from top-down games, not tilesets for platformers and that kind of confuses me when it comes to configuring the tileset on Tiled.
(Note, however, that this tileset is incomplete and Tiled will struggle to give you great shapes with it. You’re missing concave corners at the very least. In your example image, you’re using the solid brown tile as both all-ground and as a concave corner, but Tiled can only use each tile in a single scenario, it can’t use the same tile in multiple ways, unfortunately.)
Edit: I’ve written some notes on labelling terrains here, perhaps they’ll be useful. Perhaps it’ll help you understand the concepts behind terrains better, as the concepts are the same whether you’re doing top-down maps or side-scrollers.
