RemoteEvents can help you on functions that can't be interacted with from different areas. For example, you might've tried using a script but the change wouldn't show. That's because you can't just interact with stuff from everywhere. You can make a server script and a client script work together to do what you want.
Here's an example:

Server script: 

game.ReplicatedStorage.RemoteEvent:FireAllClients() or game.ReplicatedStorage.RemoteEvent:FireClient(plr)

game.ReplicatedStorage.RemoteEvent.OnServerEvent:Connect:function()

      script.Parent.Touched:Connect(function(hit)

            if hit.Parent:FindFirstChild("Humanoid") then

                  hit.Parent.Humanoid.Health = 0

            end

      end)

end)

Client script:

game.ReplicatedStorage.RemoteEvent:FireServer()

game.ReplicatedStorage.RemoteEvent.OnClientEvent:Connect:function()

      local tool = game.ReplicatedStorage.Tool:Clone()

      tool.Parent = game.Players.LocalPlayer.Backpack

      tool.Name = "YourCustomName" 

end)

These scripts will work together to turn a part into a killbrick and give the player a tool with a name of your choice.