I have started gardening just from a year ago. My back garden soil two inches below is white. Is it healthy? What needs to be done.
Impossible to tell from a photograph, has the ground been a garden for a long time? If you're in a new build on a brownfield site, the soil could be contaminated with just about anything that was used or produced on the site previously. Developers usually buy in topsoil from elsewhere to make the gardens when the houses are finished.
However, it's more likely that the whiteness is mycelium, which is a fungus that consists of very fine threads growing through the soil, there are many different kinds. Most of them are beneficial, as they help break down organic material in the soil into simpler compounds that growing plants need.