How does one check if a tool clicked on a specific part?

FIrst add RemoteEvent inside ReplicatedStorage and name it "Ore" after that add Localscript inside the tool:

local ReplicatedStorage = game:GetService("ReplicatedStorage")
local Ore = ReplicatedStorage:WaitForChild("Ore")
local Player = game.Players.LocalPlayer
local Mouse = Player:GetMouse() -- We need to get mouse (only in local script)
local Tool = script.Parent

Tool.Activated:Connect(function() -- Runs function when you click while holding the tool
	local Target = Mouse.Target -- Gets part that mouse is aiming at
	if Target then -- check if it exists
		if Target.Name == "CoalRock" then -- checks the name
			local Distance = (Player.Character.HumanoidRootPart.Position-Target.Position).Magnitude 
			if Distance < 15 then -- Checks if plyer is close
				Ore:FireServer(Target) -- fires to server
			end
		end
	end
end)

after that add Script in ServerScriptServic and paste this:

local ReplicatedStorage = game:GetService("ReplicatedStorage")
local Ore = ReplicatedStorage:WaitForChild("Ore")

Ore.OnServerEvent:Connect(function(Player,Target) -- Receives event from client
	local Distance = (Player.Character.HumanoidRootPart.Position-Target.Position).Magnitude
	if Distance < 15 then -- checks 2nd time if player is close cause you should always check this on server
		Target:Destroy() -- Destroys the target
	end	
end)

Note: Don't just copy and paste it, try to figure out what is happening, I made notes in the script