 So you don't understand auto landscape material painting, not a problem. Right click and make a new material. Call it something like auto material. Then right click that material and create a material instance. Now we need to create two material functions. To do that right click materials and textures and material function. Make one for stone and then make another one for grass. Then double click your functions and left click to drag the pen on the left into a make material attribute and plug everything in like normal. And just so we have some control over the tiling, right click landscape coordinate node, then right click again, add a multiply and drag everything together. Repeat this process for the other texture, then double click to open the master material. Drag your material functions in from your content browser, right click, break material attributes and duplicate it. Connect each break function to each break attribute, right click, linear interpolate and drag that into the base color of your main auto material. Now you will need a linear interpolate for each map that your materials are consistent of. We need one for base color, one for roughness, one for normal and ambient occlusion and drag base color from dirt into a and base color from grass into b. Right click, world aligned blend, right click, scalar parameter, name this one grass dirt sharp and duplicate it. Name it grass dirt bias and drag it into world sharpness, drag it into the world bias and drag the alpha from the world into the alpha of the lerp. Now you might notice that it's not gonna let you drag normal in without giving you an error. You don't drag it in directly. You have to drag it in from vertex normals. Then save, double click your instance, and check the bias and sharpness to make sure that they are active. Then click your landscape and drag the material instance into your landscape. If you drag your instance material into your landscape and you don't see any change, try just opening a new scene and creating a new landmass and that will usually fix it. If you go into sculpt mode and start messing around now, your material will automatically apply half the material to flat terrain and the other half to slanted. If it doesn't look like it's working, then try to double click the instance and adjusting the values of the sharp and the bias until you see a noticeable change. Hope that helps in as always. Hope you have a fantastic day and I'll see you around.