If you're starting with a tileset with regular dimensions and layout (as in your example), and your goal is to create tile maps in Tiled, there is no need to use third-party tools. Tiled supports these natively and easily.
There are a few tutorials on using Tiled like this one, but it's very simple:
- Create a new map, choose its dimensions and tile size
Add a new tileset from file, input its tile size and margin/spacing, if any (there is none in the example)
Start painting tiles. Your loaded tileset is in the sidebar.
There are also other handy features in Tiled; the trees you see in the tileset will be loaded as separate tiles, but you can use Tiled's Brush features to draw those trees in one go. There's also the Terrain Tool which helps you paint tile transitions, after you've defined the border tiles.
From there, it's best to treat the tile maps as a whole, via the frameworks that support TMX maps, rather than individual tiles. For example, you would load and render tile layers, or draw all your "wall" tiles in the same layer and perform a layer collision. There is usually no need to split a properly-authored tile set into individual tiles.