All My Textures Painting IN Squares

I don’t know why, but every single texture I try whether it be one I made (on the right, I resized it and didn’t pay attention which is the explanation for the missing parts in the corner) or one from the starter content pack (grass on the left) always paints in this stupid square shape. I got told elsewhere it’s the resolution of the landscape so I made several new ones with both max resolution and min resolution and everywhere in between with a large mix of settings but it still paints in this bloody sqaure pattern. How do I stop this?