Could you clarify if you are looking for the for crafting or a 3D vehicle mod for a specific simulation game?
Because your request mentions a file, there are a few different things you might be looking for:
You may be searching for the PDF patterns and assembly instructions used to build the physical paper model.
You might be looking for a mod file (common in games like Farming Simulator , MudRunner , or Euro Truck Simulator 2 ) that uses this specific Tatra 15 model designation.