Lichen on Conifer Branch and Dying Branches
My best guess from those photos is that you have a Norway Spruce that has an infestation of Eastern Spruce Gall Adelgid (https://pestid.msu.edu/insects-and-arthropods/eastern-spruce-gall-adelgid/). The lichen does not harm the tree, so you need not worry about it. If the tree seems otherwise healthy you may not need to treat for the adelgid either. If the tree is showing signs of distress I would need a photo of a larger portion of the tree and description of the symptoms that it is showing.