Lichen covered stone wall. The white lichens may be physcia, possibly physcia aipolia
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
Its not a Physcia as they are foliose lichens with leaf-like lobes, your photo shows a crustose lichen species.
Lat/Lng: 55.9, -3.8
OS grid ref: NS8979