How To make a digging system

I’m making a metal detecting game and need to dig holes in terrain does anyone know i can do that or anyone know a better way… That’s a specific as i can be.

True “holes” aren’t possible with the way Unity’s Terrain system works. However, if you are just talking about changing the height of terrain in a certain area, I would suggest looking at the Real-Time Terrain Deformation post on AlmostLogical.com. It is in regards to deforming terrain with explosions, but the principle is the same. There is a link to the source at the end of the article.