Coarse dust is a dust where grasses can not spread. To make Coarse Dirt you will need two things Dirt Blocks and Gravel Blocks. Please follow the following steps to make Coarse Dirt.
In order to make coarse dirt, the basic item you need to get is dirt block. So find and get at least two dirt blocks using your iron shovel.
The next required item that you will need to find and get is gravel block. Get at least two of them using your iron shovel.
Now you need to use the crafting table to craft coarse dirt blocks. Go towards the crafting table and open 3*3 crafting grid to add two gravel blocks and two dirt blocks in the same as shown in the image below. You will get four coarse dirt blocks in the right-side box of the crafting table. Add them in your “ready to use” stock.