If you download the archive and install the mod in the game FS 23, you will have a grain harvester.
In the game, you buy a Claas Tucano 580 combine, then a grain harvester for it. This will allow you to harvest your crops in the fields, or go for hire. And be sure to buy a trolley, you will need it to transport the header from the combine on it.
The Claas Tucano 580 Header and Cart wheeled harvester mod is made for harvesting in Farming Simulator 23 Mobile.