Is there a way to improve my loss of peripheral vision after a cranium surgery?

Maybe. Depends on how much peripheral loss. Sometimes prisms can expand range of field. Some people may benefit from vision therapy. Check with low vision / binocular vision experts.
Usually not. Visual field loss due to brain trauma is usually stable. Sometimes, with healing after surgery, some vision returns. If the visual loss is severe then counseling with a low vision specialist can help tremendously with adapative visual strategies. Best to see your ophthalmologist.