Does we use remote event to open gui using keybind?

my local script

local plr = game:GetService("Players").LocalPlayer
local Mouse = plr:GetMouse() 
local cas = game:GetService("ContextActionService") 


local function onEPress(name, state, input)
    if state == Enum.UserInputState.Begin then
     game.ReplicatedStorage.RemoteEvent1:FireServer()
    end
   end

cas:BindAction("ePressed", onEPress, false, Enum.KeyCode.E) -- basically when E is pressed, onEPress runs.

My script

game.ReplicatedStorage.RemoteEvent1.OnServerEvent:Connect(function()
    -- Any code in here will run when RemoteEvent is triggered
	script.Parent.Transparency = 0.5
end)

Hello RainbowBeastYT, you do not need remote event to open gui. The server should not have to know of this let alone handle gui. It's good to do it on the local script and there only because it causes less lag. Unless if you press the button all players should see it but that will be annoying to the players that try playing your game.

local plr = game:GetService("Players").LocalPlayer
local Mouse = plr:GetMouse() 
local cas = game:GetService("ContextActionService") 


local function onEPress(name, state, input)
    if state == Enum.UserInputState.Begin then
     script.Parent.BackgroundTransparency = 0.5
    end
   end

cas:BindAction("ePressed", onEPress, false, Enum.KeyCode.E) -- basically when E is pressed, onEPress runs.

Hello,

--Start
function doStuff()
	--insert code you want to do here
end
game:GetService("ContextActionService"):BindAction("ExecuteCode", doStuff, false, "f") --if F is pressed it will run the doStuff()
--End

~Frag