How to get textures without a camera

Some textures have me stumped like finding a seamless american sidewalk. Is there a effective way of converting angled images into flat images for textures? I don’t have much experience in photoshop yet. Does anyone know where I should look for information on this?

idk what you are really asking, but try the mapping modifier. Modifiers–>really left side.

If not, then go to the uv tab in edit mode and select all. Then after you have selected whole thing, rotate it to fit the picture. You can also scale it.

I’m not sure if it helped