How can I detect whether a player can see an object or not?

Here I'll help u out

Btw this was done by IPad so sorry if there were any errors or simple mistakes

Make a local script put In startergui

local Player = game.Playera.LocalPlayer
local Camera = Workspace.CurrentCamera
local FOV = Camera.FieldOfView -- FOV = FieldOfView
local Parts = {} -- leave empty if u don't know what u are doing

Scan = function(object)
  for i, v in pairs(object:GetChildren()) do
   table.insert(Parts, v)
   if #v:GetChildren() > 0 then
    Scan(v) -- scan the object since it has children
  end
 end
end

Scan(Workspace) -- this will scan everything in the workspace

function getNearestObject()
   for i, v in pairs(Parts) do
      if (Player.Character.Torso.Position - v.Position).magnitude < FOV then -- magnitude gets the distance between the 2 points
        return v
      end
   end
end

while wait() do -- continuos loop
   local object = getNearestObject()
   print(object.Name) -- objects name goes towards output
end